JavaScript Variables and Data Types Quiz

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Questions and Answers

Which statement about 'const' variables is true?

They can be created without initial values.

They must be initialized when declared. (correct)

They can be reassigned after declaration.

They can hold variables of any type, including objects.

What does the following ternary operator do? const allowed = ageDrink >= 18 ? 'wine' : 'water';

It checks if the input age is numeric.

It sets a default drink regardless of age.

It determines drink eligibility based on age. (correct)

It checks if wine is available or not.

In JavaScript, which of the following is considered a falsy value?

'0'

'Hello'

'false'

'NaN' (correct)

What will happen if you attempt to reassign a variable declared with const?

It will result in an error. Signup and view all the answers

What are template literals used for in JavaScript?

To create multi-line strings and interpolate variables. Signup and view all the answers

What will happen if you attempt to reassign a const variable?

It will result in an error. Signup and view all the answers

Which statement about type coercion is accurate?

It can occur automatically during string concatenation. Signup and view all the answers

Which of the following correctly demonstrates string concatenation?

console.log('Age: ' + 25); Signup and view all the answers

Which conditional structure is used for multi-branch statements in JavaScript?

switch case statements. Signup and view all the answers

What does the ‘+’ operator do when used with strings in JavaScript?

It concatenates the strings together. Signup and view all the answers

What does the expression '23' - '10' return in JavaScript?

13 Signup and view all the answers

Which statement about truthy and falsy values is correct?

undefined is a falsy value. Signup and view all the answers

Which scenario best illustrates the use of a switch case statement?

Checking the current day of the week. Signup and view all the answers

What does the ternary operator evaluate in the statement const allowed = ageDrink >= 18 ? 'wine' : 'water';?

Whether to allow access to 'wine' or 'water' based on age. Signup and view all the answers

Which function would you use to explicitly convert a string to a number?

Number() Signup and view all the answers

What will the condition in an if statement execute if the condition evaluates to false?

The else block will execute, if present. Signup and view all the answers

What is one of the primary uses of the let keyword in JavaScript?

To create a variable with block scope. Signup and view all the answers

What will be the output of the statement console.log(typeof population);?

Number Signup and view all the answers

Why will the statement const job; result in an error?

const variables require initialization when declared. Signup and view all the answers

Which of the following shows the correct use of string and template literals to display a message?

console.log(<code>${country} is in ${continent}.</code>); Signup and view all the answers

Which JavaScript feature allows you to declare a variable with scope limited to its block?

let Signup and view all the answers

What is the output of console.log(colour); after declaring const colour = 'red';?

'red' Signup and view all the answers

What is the output of the expression '23' + '10' + 3 in JavaScript?

23103 Signup and view all the answers

What is printed when Boolean(undefined) is executed?

false Signup and view all the answers

What value will be assigned to 'allowed' if ageDrink is 17?

'water' Signup and view all the answers

What is the value of the expression '23' * '10' * 3?

690 Signup and view all the answers

What does the expression Boolean({}) evaluate to?

true Signup and view all the answers

In the provided code, what happens if the variable year is of type string initially?

It can be converted to a number using Number(year). Signup and view all the answers

What is the outcome of the expression '30' / '10' / 3?

1 Signup and view all the answers

How does logical operators behave in JavaScript according to the given information?

They are similar to Java. Signup and view all the answers

What will be logged to the console if BMIMark is 24 and BMIJonas is 26?

John's BMI 26 is higher than Mark's! Signup and view all the answers

What is the output of the statement `console.log('30' / '10' / 3);`?

1 Signup and view all the answers

Which of the following statements is true regarding truthy values in JavaScript?

Boolean(100) returns true Signup and view all the answers

Which statement describes the difference between type conversion and type coercion?

Type conversion is always performed by the programmer, whereas type coercion happens automatically. Signup and view all the answers

What will be outputted if `console.log('23' + '10' + 3);` is executed?

23103 Signup and view all the answers

What is the result of the expression `Boolean({})`?

true Signup and view all the answers

What will `console.log(typeof(Number(year)));` output if year is '1999'?

number Signup and view all the answers

If AgeDrink holds a value of 20, what will console.log output after evaluating `const allowed = ageDrink >= 18 ? 'wine' : 'water';`?

You are allowed to drink wine. Signup and view all the answers

What will be the data type of the variable 'population' after it has been declared and assigned the value 200000000?

Number Signup and view all the answers

What happens when you try to change the value of a variable declared with 'const'?

An error is thrown. Signup and view all the answers

Which statement is true regarding the output of the expression `console.log(`${country} is a country in ${continent} and has a population of ${population}.`);`?

It uses template literals correctly. Signup and view all the answers

What will be the output of the console.log statement `console.log(colour);` after declaring `const colour = 'red';`?

'red' Signup and view all the answers

What data type will the variable 'age' be after executing the lines `let age; age = 30;`?

Number Signup and view all the answers

Which statement about the variable 'age' is correct after declaring `let age; age = 30;` followed by `age = 31;`?

'age' can be initialized multiple times. Signup and view all the answers

What will be the outcome of the statement `console.log(typeof country);` given `let country = 'Nigeria';`?

'String' Signup and view all the answers

Which of the following expressions correctly demonstrates the behavior of `let` and `const` in JavaScript?

<code>let</code> can change its value, while <code>const</code> cannot. Signup and view all the answers

What result will be produced by the expression '0' - 1 in JavaScript?

-1 Signup and view all the answers

Which scenario correctly illustrates the utility of template literals?

console.log(<code>Hello ${name}</code>); Signup and view all the answers

In which case would a switch statement NOT be the best option?

When comparing a numeric value to multiple ranges. Signup and view all the answers

What will be the output of the console.log statement if massJonas is 78 and heightJonas is 1.8?

24.07 Signup and view all the answers

Which of the following describes the primary difference between let and const?

Const variables must be initialized upon declaration, while let can be initialized later. Signup and view all the answers

What will happen if prompt-sync attempts to capture an input of a non-numeric type when using Number()?

Input will be converted to NaN. Signup and view all the answers

What is the likely output if you execute the expression Boolean('Hello')?

true Signup and view all the answers

If you use the expression heightJonas ** 2 with heightJonas as 1.8, what will the result be?

2.56 Signup and view all the answers

What is the result of trying to reassign a value to a variable declared with let if it was not initially initialized?

It will assign the new value successfully. Signup and view all the answers

Which of the following is an example of conditional execution of code using nested if statements?

if (BMIJonas > 25) { if (BMIJonas > BMIJohn) { //code } } Signup and view all the answers

What type of value will be returned when evaluating Boolean(null)?

false Signup and view all the answers

Which of the following correctly assigns a multi-line string using template literals?

const message = <code>Hello World</code>; Signup and view all the answers

What will be logged on the console after executing console.log(`${undefined}`);?

undefined Signup and view all the answers

What will happen if a Boolean expression such as const markHigherBMI = BMIMark < BMIJonas; is true?

markHigherBMI will be true. Signup and view all the answers

Which of the following demonstrates the correct use of a switch case statement with a default case?

switch (value) { case value1: // code; default: // default code; } Signup and view all the answers

What will the following statement return: console.log('100' * '10' + '20');?

'1020' Signup and view all the answers

What does the expression '10' + 5 - 5 yield?

15 Signup and view all the answers

In the context of variable declaration, what will be the data type of variable strategically assigned a numeric string and then a number, e.g., let age; age = '30'; age = 40;

Number Signup and view all the answers

Which of the following expressions will demonstrate the difference between type conversion and type coercion distinctly?

const sum = Number('5') + 5; Signup and view all the answers

What will the following statement print: console.log(0 == '0');?

true Signup and view all the answers

When executing an expression that coerces a number into a string using the subtraction operator, what would the output be?

Results in NaN. Signup and view all the answers

Which statement best describes the primary difference between let and const in regards to variable assignment?

Let allows reassignment while const must be assigned on initialization only. Signup and view all the answers

What will be the output when execution reaches the line where 'Give in a day' prompt is called?

The output will be the user's input in lowercase. Signup and view all the answers

Which statement best describes the 'prompt-sync' import in the given code?

It allows interaction with the console for input without synchronizing with asynchronous code. Signup and view all the answers

If the code is executed with the input 'Monday', what will the variable 'day' contain after running the prompt command?

The string 'monday' Signup and view all the answers

What will happen if the 'prompt' function fails to receive any input?

It will return an empty string. Signup and view all the answers

What distinguishes 'const' from 'let' in regard to variable assignments in JavaScript?

Variables defined with 'const' cannot be reassigned after initial value assignment. Signup and view all the answers

Study Notes

Variables and Data Types

Variables in JavaScript can be declared with let (reassignable) and const (non-reassignable).
Example of variable declaration: let country = 'Nigeria'.
JavaScript data types include strings, numbers (integer or float), booleans (true/false), undefined, objects, and symbols.

Constants and Reassignment

const variables must be initialized at declaration and cannot be reassigned.
Example: const colour = 'red' will throw an error on reassignment such as colour = 'yellow'.

String Concatenation and Template Literals

Strings are concatenated using the + operator.
Example: console.log(country + ' has a population of ' + population + '.');
Template literals, enclosed in backticks (``), support multi-line strings and easy variable interpolation.
Example: console.log(countryisacountryin{country} is a country in countryisacountryin{continent} and has a population of ${population}.);

Calculating Body Mass Index (BMI)

BMI calculation formula: mass divided by the square of height.
Example: const BMIJonas = massJonas / heightJonas ** 2;
BMI comparison using boolean expressions.
Example: const markHigherBMI = BMIMark > BMIJonas;

Conditional Statements

if statements allow for conditional execution of code.

Basic structure of an if-else statement:

if (condition) {
    // code to execute if true
} else {
    // code to execute if false
}

Type Conversion and Coercion

Type conversion: explicitly changing a variable's type using functions like Number().
Type coercion: automatic conversion during operations; e.g., subtracting strings converts them to numbers: '23' - '10' equals 13.

Truthy and Falsy Values

Falsy values include: 0, undefined, null, NaN, and empty strings ('').
Truthy values are all other values, such as 100, 'Jonas', and empty objects ({}).

Switch Case Statements

Switch statements enable multi-branch execution based on a variable's value.
Syntax involves defining cases with corresponding actions and a default case for unhandled values.

Ternary Operators

Ternary operators offer a concise syntax for if-else statements.
Example: const allowed = ageDrink >= 18 ? 'wine' : 'water'; determines drink eligibility based on age.

Practical Input Handling

The prompt-sync module facilitates synchronous user input in Node.js for interactive data gathering.
Example: const ageDrink = prompt('How old are you?'); captures user age input.

Variables and Data Types

Variables in JavaScript can be declared using let and const. let allows reassignment, while const does not.
Example of variable declaration: let country = 'Nigeria' assigns 'Nigeria' to country.
Data types include strings (text), numbers (integer or float), boolean (true/false), undefined, object, and symbol.

Constants and Reassignment

const variables require initialization upon declaration and cannot be reassigned. Example: const colour = 'red'.
Attempting to reassign a const variable, like colour = 'yellow', will result in an error.

String Concatenation and Template Literals

Strings can be concatenated using the + operator, e.g., console.log(country + ' has a population of ' + population + '.').
Template literals using backticks (`) allow for multi-line strings and easy variable interpolation:
- Example:
```
console.log(`${country} is a country in ${continent} and has a population of ${population}.`);
```

Calculating Body Mass Index (BMI)

BMI is calculated as mass divided by the square of height:
- Example: const BMIJonas = massJonas / heightJonas ** 2;
A comparison between two BMIs can be made using a boolean expression, e.g., const markHigherBMI = BMIMark > BMIJonas;.

Conditional Statements

if statements are used for conditional execution of code, e.g., comparing BMIs to print which is higher.

Basic structure:

if (condition) {
    // code to execute if true
} else {
    // code to execute if false
}

Type Conversion and Coercion

Type conversion changes a variable from one type to another explicitly using functions like Number().
Type coercion automatically converts types during operations, e.g.:
- Subtraction or multiplication of strings converts them to numbers: '23' - '10' equals 13.

Truthy and Falsy Values

Falsy values: 0, undefined, null, NaN, '' (empty string).
Truthy values: All other values are considered true, e.g., 100, 'Jonas', and {} (empty object) are truthy.

Switch Case Statements

Use switch cases for multi-branch statements based on the value of a variable, e.g., checking the day of the week.
Syntax includes defining cases followed by corresponding actions and a default case for unmatched values.

Ternary Operators

Ternary operators provide a shorthand syntax for if-else statements:
- Example: const allowed = ageDrink >= 18 ? 'wine' : 'water'; determines drink eligibility based on age.

Practical Input Handling

The prompt-sync module allows synchronous user input in Node.js, making it easier to interactively gather user data.
Example prompt: const ageDrink = prompt('How old are you?'); captures the user's age input.

Variables and Data Types

Variables in JavaScript can be declared using let and const. let allows reassignment, while const does not.
Example of variable declaration: let country = 'Nigeria' assigns 'Nigeria' to country.
Data types include strings (text), numbers (integer or float), boolean (true/false), undefined, object, and symbol.

Constants and Reassignment

const variables require initialization upon declaration and cannot be reassigned. Example: const colour = 'red'.
Attempting to reassign a const variable, like colour = 'yellow', will result in an error.

String Concatenation and Template Literals

Strings can be concatenated using the + operator, e.g., console.log(country + ' has a population of ' + population + '.').
Template literals using backticks (`) allow for multi-line strings and easy variable interpolation:
- Example:
```
console.log(`${country} is a country in ${continent} and has a population of ${population}.`);
```

Calculating Body Mass Index (BMI)

BMI is calculated as mass divided by the square of height:
- Example: const BMIJonas = massJonas / heightJonas ** 2;
A comparison between two BMIs can be made using a boolean expression, e.g., const markHigherBMI = BMIMark > BMIJonas;.

Conditional Statements

if statements are used for conditional execution of code, e.g., comparing BMIs to print which is higher.

Basic structure:

if (condition) {
    // code to execute if true
} else {
    // code to execute if false
}

Type Conversion and Coercion

Type conversion changes a variable from one type to another explicitly using functions like Number().
Type coercion automatically converts types during operations, e.g.:
- Subtraction or multiplication of strings converts them to numbers: '23' - '10' equals 13.

Truthy and Falsy Values

Falsy values: 0, undefined, null, NaN, '' (empty string).
Truthy values: All other values are considered true, e.g., 100, 'Jonas', and {} (empty object) are truthy.

Switch Case Statements

Use switch cases for multi-branch statements based on the value of a variable, e.g., checking the day of the week.
Syntax includes defining cases followed by corresponding actions and a default case for unmatched values.

Ternary Operators

Ternary operators provide a shorthand syntax for if-else statements:
- Example: const allowed = ageDrink >= 18 ? 'wine' : 'water'; determines drink eligibility based on age.

Practical Input Handling

The prompt-sync module allows synchronous user input in Node.js, making it easier to interactively gather user data.
Example prompt: const ageDrink = prompt('How old are you?'); captures the user's age input.

Variables and Data Types

Variables in JavaScript can be declared using let for mutable variables and const for immutable ones.
Example declaration: let country = 'Nigeria'; assigns 'Nigeria' to the variable country.
JavaScript data types include:
- Strings: Textual data
- Numbers: Integers and floats
- Booleans: True or false values
- Undefined: Value not assigned
- Objects: Collections of properties
- Symbols: Unique identifiers

Constants and Reassignment

const variables must be initialized during declaration and cannot be reassigned.
Example: Trying to reassign const colour = 'red'; to colour = 'yellow'; results in an error.

String Concatenation and Template Literals

Strings can be concatenated using the + operator.
- Example: console.log(country + ' has a population of ' + population + '.');
Template literals, enclosed in backticks (``), allow for multi-line strings and interpolation of variables.
- Example: console.log(countryisacountryin{country} is a country in countryisacountryin{continent} and has a population of ${population}.);

Calculating Body Mass Index (BMI)

BMI is calculated using the formula: mass divided by the square of height.
- Example: const BMIJonas = massJonas / heightJonas ** 2;
BMI comparisons can be made using boolean expressions.
- Example: const markHigherBMI = BMIMark > BMIJonas;

Conditional Statements

if statements facilitate conditional code execution.

Basic structure:

if (condition) {
    // code to execute if true
} else {
    // code to execute if false
}

Type Conversion and Coercion

Type conversion: Explicitly change a variable's type using functions such as Number().
Type coercion: Automatic conversion that occurs during operations, for example:
- '23' - '10' results in 13, as strings convert to numbers during subtraction.

Truthy and Falsy Values

Falsy values include: 0, undefined, null, NaN, and '' (empty string).
Truthy values encompass all other values, including 100, 'Jonas', and {} (empty object).

Switch Case Statements

Use switch statements for multiple branching based on a variable's value.
Syntax includes defining cases and a default case for unhandled values.

Ternary Operators

Ternary operators offer a shorthand for if-else statements.
- Example: const allowed = ageDrink >= 18 ? 'wine' : 'water'; determines drink eligibility based on age.

Practical Input Handling

prompt-sync module allows synchronous user input in Node.js for easy data collection.
- Example: const ageDrink = prompt('How old are you?'); captures the user's age input.

Practical Input Handling

The prompt-sync module enables synchronous user input in Node.js for interactive applications.
Example usage: const ageDrink = prompt('How old are you?'); captures the user's age.

Variables and Data Types

JavaScript allows variable declaration using let (reassignable) and const (non-reassignable).
Example declaration: let country = 'Nigeria';.
JavaScript supports various data types, including:
- Strings (text)
- Numbers (integers and floats)
- Booleans (true/false)
- Undefined
- Objects
- Symbols

Constants and Reassignment

const variables must be initialized during declaration and cannot be reassigned.
Attempting to reassign a const variable leads to an error; for example, const colour = 'red'; cannot be changed with colour = 'yellow';.

String Concatenation and Template Literals

Strings can be combined using the + operator. For example: console.log(country + ' has a population of ' + population + '.');
Template literals, enclosed in backticks (``), allow multi-line strings and easier variable interpolation, e.g.,:
- console.log(${country} is a country in ${continent} and has a population of ${population}.);

Calculating Body Mass Index (BMI)

BMI is computed as mass divided by the square of height, expressed as:
- const BMIJonas = massJonas / heightJonas ** 2;
Comparisons can be made using boolean expressions, e.g., const markHigherBMI = BMIMark > BMIJonas;.

Conditional Statements

if statements facilitate conditional code execution. Basic structure:

if (condition) {
    // code to execute if true
} else {
    // code to execute if false
}

Type Conversion and Coercion

Type conversion is an explicit change of a variable's type using functions like Number().
Type coercion occurs automatically during operations, for instance:
- Subtracting or multiplying strings converts them to numbers ('23' - '10' results in 13).

Truthy and Falsy Values

Falsy values in JavaScript: 0, undefined, null, NaN, and '' (empty string).
Truthy values include everything else, such as 100, 'Jonas', and {} (empty object).

Switch Case Statements

A switch statement provides a multi-branch selection based on a variable's value.
Syntax includes defining cases with corresponding actions and a default for unmatched values.

Ternary Operators

Ternary operators offer a shorthand for if-else statements.
Example: const allowed = ageDrink >= 18 ? 'wine' : 'water'; determines drink eligibility based on age.

Example Code Snippets

Comparing BMIs:

if (BMIMark > BMIJonas) {
    console.log(`Mark's BMI ${BMIMark} is higher than John's!`);
} else {
    console.log(`John's BMI ${BMIJonas} is higher than Mark's!`);
}

Demonstrating type conversion:

const year = '1999';
console.log(typeof(Number(year))); // converts string to number

Conclusion

JavaScript features a robust structure for handling variables, data types, input, and conditional logic, enhancing programmability while ensuring efficient data manipulation.### Variable Declaration and Data Types
let allows reassignment of variables, while const does not.
Example: let country = 'Nigeria' assigns 'Nigeria' to the variable country.
JavaScript supports multiple data types including strings, numbers (integers or floats), booleans (true/false), undefined, objects, and symbols.

Constants and Reassignment

const variables must be initialized upon declaration and cannot be reassigned later.
Example: const colour = 'red' cannot be changed to colour = 'yellow', which would throw an error.

String Concatenation and Template Literals

Strings can be combined using the + operator, e.g., console.log(country + ' has a population of ' + population + '.').
Template literals use backticks (`) for multi-line strings and facilitate easy variable interpolation:
- Example: console.log(${country} is a country in ${continent} and has a population of ${population}.).

Body Mass Index (BMI) Calculation

BMI is computed as mass divided by the square of height:
- Example: const BMIJonas = massJonas / (heightJonas ** 2).
Compare BMIs using a boolean expression, e.g., const markHigherBMI = BMIMark > BMIJonas.

Conditional Statements

if statements execute code based on conditions. Basic structure:

if (condition) {
    // code to execute if true
} else {
    // code to execute if false
}

Type Conversion and Coercion

Type conversion explicitly changes variable types using functions like Number().
Type coercion automatically converts types during operations, e.g., subtracting strings: '23' - '10' results in 13.

Truthy and Falsy Values

Falsy values include: 0, undefined, null, NaN, and empty strings ('').
Truthy values encompass all others, e.g., 100, 'Jonas', and empty objects ({}) are considered true.

Switch Case Statements

switch statements handle multi-branch conditions based on variable values, such as checking the day of the week.
Syntax involves defining cases followed by actions and a default case for unmatched values.

Ternary Operators

Ternary operators act as shorthand for if-else statements.
Example: const allowed = ageDrink >= 18 ? 'wine' : 'water' determines drink eligibility based on age.

Practical Input Handling

The prompt-sync module enables synchronous user input in Node.js for interactive data collection.
Example: const ageDrink = prompt('How old are you?') captures the user's age input.
User input can be processed by converting it to a specific format, e.g., const day = prompt('Give in a day: ').toLowerCase().

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Test your knowledge on variables and data types in JavaScript. This quiz covers topics such as variable declaration, constants, string manipulation, and more. Perfect for beginners looking to solidify their understanding of JavaScript basics.

JavaScript Variables and Data Types Quiz

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Questions and Answers

Which statement about 'const' variables is true?

What does the following ternary operator do? const allowed = ageDrink >= 18 ? 'wine' : 'water';

In JavaScript, which of the following is considered a falsy value?

What will happen if you attempt to reassign a variable declared with const?

What are template literals used for in JavaScript?

What will happen if you attempt to reassign a const variable?

Which statement about type coercion is accurate?

Which of the following correctly demonstrates string concatenation?

Which conditional structure is used for multi-branch statements in JavaScript?

What does the ‘+’ operator do when used with strings in JavaScript?

What does the expression '23' - '10' return in JavaScript?

Which statement about truthy and falsy values is correct?

Which scenario best illustrates the use of a switch case statement?

What does the ternary operator evaluate in the statement const allowed = ageDrink >= 18 ? 'wine' : 'water';?

Which function would you use to explicitly convert a string to a number?

What will the condition in an if statement execute if the condition evaluates to false?

What is one of the primary uses of the let keyword in JavaScript?

What will be the output of the statement console.log(typeof population);?

Why will the statement const job; result in an error?

Which of the following shows the correct use of string and template literals to display a message?

Which JavaScript feature allows you to declare a variable with scope limited to its block?

What is the output of console.log(colour); after declaring const colour = 'red';?

What is the output of the expression '23' + '10' + 3 in JavaScript?

What is printed when Boolean(undefined) is executed?

What value will be assigned to 'allowed' if ageDrink is 17?

What is the value of the expression '23' * '10' * 3?

What does the expression Boolean({}) evaluate to?

In the provided code, what happens if the variable year is of type string initially?

What is the outcome of the expression '30' / '10' / 3?

How does logical operators behave in JavaScript according to the given information?

What will be logged to the console if BMIMark is 24 and BMIJonas is 26?

What is the output of the statement console.log('30' / '10' / 3);?

Which of the following statements is true regarding truthy values in JavaScript?

Which statement describes the difference between type conversion and type coercion?

What will be outputted if console.log('23' + '10' + 3); is executed?

What is the result of the expression Boolean({})?

What will console.log(typeof(Number(year))); output if year is '1999'?

If AgeDrink holds a value of 20, what will console.log output after evaluating const allowed = ageDrink >= 18 ? 'wine' : 'water';?

What will be the data type of the variable 'population' after it has been declared and assigned the value 200000000?

What happens when you try to change the value of a variable declared with 'const'?

Which statement is true regarding the output of the expression console.log(${country} is a country in ${continent} and has a population of ${population}.);?

What will be the output of the console.log statement console.log(colour); after declaring const colour = 'red';?

What data type will the variable 'age' be after executing the lines let age; age = 30;?

Which statement about the variable 'age' is correct after declaring let age; age = 30; followed by age = 31;?

What will be the outcome of the statement console.log(typeof country); given let country = 'Nigeria';?

Which of the following expressions correctly demonstrates the behavior of let and const in JavaScript?

What result will be produced by the expression '0' - 1 in JavaScript?

Which scenario correctly illustrates the utility of template literals?

In which case would a switch statement NOT be the best option?

What will be the output of the console.log statement if massJonas is 78 and heightJonas is 1.8?

Which of the following describes the primary difference between let and const?

What will happen if prompt-sync attempts to capture an input of a non-numeric type when using Number()?

What is the likely output if you execute the expression Boolean('Hello')?

If you use the expression heightJonas ** 2 with heightJonas as 1.8, what will the result be?

What is the result of trying to reassign a value to a variable declared with let if it was not initially initialized?

Which of the following is an example of conditional execution of code using nested if statements?

What type of value will be returned when evaluating Boolean(null)?

Which of the following correctly assigns a multi-line string using template literals?

What will be logged on the console after executing console.log(${undefined});?

What will happen if a Boolean expression such as const markHigherBMI = BMIMark < BMIJonas; is true?

Which of the following demonstrates the correct use of a switch case statement with a default case?

What will the following statement return: console.log('100' * '10' + '20');?

What does the expression '10' + 5 - 5 yield?

In the context of variable declaration, what will be the data type of variable strategically assigned a numeric string and then a number, e.g., let age; age = '30'; age = 40;

Which of the following expressions will demonstrate the difference between type conversion and type coercion distinctly?

What will the following statement print: console.log(0 == '0');?

When executing an expression that coerces a number into a string using the subtraction operator, what would the output be?

Which statement best describes the primary difference between let and const in regards to variable assignment?

What will be the output when execution reaches the line where 'Give in a day' prompt is called?

Which statement best describes the 'prompt-sync' import in the given code?

If the code is executed with the input 'Monday', what will the variable 'day' contain after running the prompt command?

What will happen if the 'prompt' function fails to receive any input?

What distinguishes 'const' from 'let' in regard to variable assignments in JavaScript?

Study Notes

Variables and Data Types

Constants and Reassignment

What is the output of the statement `console.log('30' / '10' / 3);`?

What will be outputted if `console.log('23' + '10' + 3);` is executed?

What is the result of the expression `Boolean({})`?

What will `console.log(typeof(Number(year)));` output if year is '1999'?

If AgeDrink holds a value of 20, what will console.log output after evaluating `const allowed = ageDrink >= 18 ? 'wine' : 'water';`?

Which statement is true regarding the output of the expression `console.log(`${country} is a country in ${continent} and has a population of ${population}.`);`?

What will be the output of the console.log statement `console.log(colour);` after declaring `const colour = 'red';`?

What data type will the variable 'age' be after executing the lines `let age; age = 30;`?

Which statement about the variable 'age' is correct after declaring `let age; age = 30;` followed by `age = 31;`?

What will be the outcome of the statement `console.log(typeof country);` given `let country = 'Nigeria';`?

Which of the following expressions correctly demonstrates the behavior of `let` and `const` in JavaScript?

What will be logged on the console after executing console.log(`${undefined}`);?