JavaScript

Question 1

Inside which HTML element do we put the JavaScript?

Accepted Answer

Answer

Answer

Answer

<js>

Question 2

What is the correct syntax for referring to an external script called "xxx.js"?

Accepted Answer

Answer

Answer

Question 3

The external JavaScript file must contain the <script> tag.

Accepted Answer

False

Answer

True

Question 4

How do you write "Hello World" in an alert box?

Accepted Answer

alert("Hello World");

Answer

alertBox("Hello World");

Answer

msgBox("Hello World");

Answer

msg("Hello World");

Question 5

How do you create a function in JavaScript?

Accepted Answer

function myFunction()

Answer

function = myFunction()

Answer

function:myFunction()

Question 6

How do you call a function named "myFunction"?

Accepted Answer

myFunction()

Answer

call myFunction()

Answer

call function myFunction()

Question 7

How to write an IF statement in JavaScript?

Accepted Answer

if (i == 5)

Answer

if i = 5 then

Answer

if i = 5

Answer

if i == 5 then

Question 8

How to write an IF statement for executing some code if "i" is NOT equal to 5?

Accepted Answer

if (i != 5)

Answer

if i =! 5 then

Answer

if (i <> 5)

Answer

if i <> 5

Question 9

How does a FOR loop start?

Accepted Answer

for (i = 0; i <= 5; i++)

Answer

for (i <= 5; i++)

Answer

for (i = 0; i <= 5)

Answer

for i = 1 to 5

Question 10

What is the correct way to write a JavaScript array?

Accepted Answer

var colors = ["red", "green", "blue"]

Answer

var colors = "red", "green", "blue"

Answer

var colors = (1:"red", 2:"green", 3:"blue")

Answer

var colors = 1 = ("red"), 2 = ("green"), 3 = ("blue")

Question 11

What is the correct JavaScript syntax for opening a new window called "w2" ?

Accepted Answer

w2 = window.open("http://www.w3schools.com");

Answer

w2 = window.new("http://www.w3schools.com");

Question 12

JavaScript is the same as Java.

Accepted Answer

False.

Answer

True.

Question 13

How can you detect the client's browser name?

Accepted Answer

navigator.appName

Answer

browser.name

Answer

client.navName

Question 14

How do you declare a JavaScript variable?

Accepted Answer

var carName;

Answer

v carName;

Answer

variable carName;

Question 15

Which operator is used to assign a value to a variable?

Accepted Answer

=

Answer

-

Answer

x

Answer

*

Question 16

What will the following code return: Boolean(10 > 9)

Accepted Answer

true

Answer

NaN

Answer

false

Question 17

Is JavaScript case-sensitive?

Accepted Answer

Yes

Answer

No

Question 18

Where is the correct place to insert a JavaScript?

Accepted Answer

Both the section and the section are correct

Answer

The <head> section

Answer

The <body> section

Question 19

How does a WHILE loop start?

Accepted Answer

while (i <= 10)

Answer

while (i <= 10; i++)

Answer

while i = 1 to 10

Question 20

How can you add a comment in a JavaScript?

Accepted Answer

//This is a comment

Answer

Answer

'This is a comment

Question 21

Which event occurs when the user clicks on an HTML element?

Accepted Answer

onclick

Answer

onmouseclick

Answer

onchange

Answer

onmouseover

Question 22

What is the correct JavaScript syntax to change the content of the HTML element below?

This is a demonstration.

Accepted Answer

document.getElementById("demo").innerHTML = "Hello World!";

Answer

#demo.innerHTML = "Hello World!";

Answer

document.getElementByName("p").innerHTML = "Hello World!";

Answer

document.getElement("p").innerHTML = "Hello World!";

Question 23

How to insert a comment that has more than one line?

Accepted Answer

/*This comment has
more than one line*/

Answer

//This comment has
more than one line//

Answer

Question 24

How do you round the number 7.25, to the nearest integer?

Accepted Answer

Math.round(7.25)

Answer

round(7.25)

Answer

rnd(7.25)

Answer

Math.rnd(7.25)

Question 25

How do you find the number with the highest value of x and y?

Accepted Answer

Math.max(x, y)

Answer

ceil(x, y)

Answer

Math.ceil(x, y)

Answer

top(x, y)

Question 26

Given a number of elements that need to stay in order, would you use an Object or an Array?

Accepted Answer

Array

Answer

Object

Question 27

Given a collection of artists and lists of their songs, would you store the artist-song-list pairs in an Object or an Array?

Accepted Answer

Object

Answer

Array

Question 28

True or false: All the elements in an array must be of the same type.

Accepted Answer

False

Answer

True

Question 29

True or false: All keys in an object are strings.

Accepted Answer

True

Answer

False

Question 30

What happens to the array in the following code snippet?

const dogs = ["Fido", "Odie", "Oscar"]

dogs.length

dogs.length = 1

Accepted Answer

The array becomes just ["Fido"]

Answer

Nothing

Answer

The array becomes just ["Oscar"]

Answer

The array becomes just ["Odie", "Oscar"]

Question 31

What are the keys in the object after running the code below?
const artistsAndSongs = {
  'Prince': ["Purple Rain", "When Doves Cry"],
  'The Beatles': ["Revolution", "Norwegian Wood"],
  'Joni Mitchell': ["A Case of You", "Sunny Sunday"],
  'Justin Bieber': ["Baby"]
}

artistsAndSongs['Daft Punk'] = ["Harder, Better, Faster, Stronger"]

delete artistsAndSongs["Justin Bieber"]

Accepted Answer

['Prince', 'The Beatles', 'Joni Mitchell', 'Daft Punk']

Answer

['Prince', 'The Beatles', 'Joni Mitchell', 'Justin Bieber', 'Daft Punk']

Answer

['Prince', 'The Beatles', 'Joni Mitchell', 'Justin Bieber']

Answer

['Prince', 'The Beatles', 'Joni Mitchell']

Question 32

If we run artistsAndSongs['Daft Punk'].push("Around the World") after running the code below, what is the value of the object?
const artistsAndSongs = {
  'Prince': ["Purple Rain", "When Doves Cry"],
  'The Beatles': ["Revolution", "Norwegian Wood"],
  'Joni Mitchell': ["A Case of You", "Sunny Sunday"],
  'Justin Bieber': ["Baby"]
}

artistsAndSongs['Daft Punk'] = ["Harder, Better, Faster, Stronger"]

delete artistsAndSongs["Justin Bieber"]

Accepted Answer

const artistsAndSongs = {
 'Prince': ["Purple Rain", "When Doves Cry"],
 'The Beatles': ["Revolution", "Norwegian Wood"],
 'Joni Mitchell': ["A Case of You", "Sunny Sunday"],
 'Daft Punk': ["Harder, Better, Faster, Stronger", "Around the World"]
}

Answer

const artistsAndSongs = {
 'Prince': ["Purple Rain", "When Doves Cry"],
 'The Beatles': ["Revolution", "Norwegian Wood"],
 'Joni Mitchell': ["A Case of You", "Sunny Sunday"],
 'Daft Punk': ["Harder, Better, Faster, Stronger"]
}

Answer

const artistsAndSongs = {
 'Prince': ["Purple Rain", "When Doves Cry"],
 'The Beatles': ["Revolution", "Norwegian Wood"],
 'Joni Mitchell': ["A Case of You", "Sunny Sunday"],
 'Daft Punk': ["Around the World"]
}

Answer

const artistsAndSongs = {
 'Prince': ["Purple Rain", "When Doves Cry"],
 'The Beatles': ["Revolution", "Norwegian Wood"],
 'Joni Mitchell': ["A Case of You", "Sunny Sunday"]
}

Question 33

What is the result of the following code in a browser that supports the spread operator?
const oneTwoThree = [1, 2, 3]
const sevenEightNine = [7, 8, 9]

[4, 5, 6, ...oneTwoThree, ...sevenEightNine]

Accepted Answer

[4, 5, 6, 1, 2, 3, 7, 8, 9]

Answer

[4, 5, 6, 7, 8, 9, 1, 2, 3]

Answer

[1, 2, 3, 4, 5, 6, 7, 8, 9]

Answer

Error

Question 34

Given the array const letters = ["alpha", "gamma", "delta"], which operation(s) return the array ["alpha", "beta", "gamma", "delta"]?

Accepted Answer

[...letters.slice(0, 1), 'beta', ...letters.slice(1)]

Answer

letters.push("beta")

Answer

letters.unshift('beta')

Answer

letters.splice(1, 1, 'beta')

Answer

letters.splice(1, 0, 'beta')

Question 35

What does the following function call log to console:
function log() {
  console.log(greeting);
  var greeting = 'Hello!';
}
log();

Accepted Answer

undefined

Answer

'Hello!'

Answer

'undefined is not a function'

Question 36

What does the following function call log to console:
log();
function log() {
  console.log(greeting);
  var greeting = 'Hello!';
}

Accepted Answer

undefined

Answer

'Hello!'

Answer

'undefined is not a function'

Question 37

What does the following function call log to console:
log();
var log = function() {
  console.log(greeting);
  var greeting = 'Hello!';
}

Accepted Answer

'log is not a function'

Answer

'Hello!'

Answer

undefined

Question 38

What does the following function log to console:
function log(s) {
  var s = 'Mr. X';
  console.log(s);
}
log('Hello!');

Accepted Answer

'Mr. X'

Answer

'Hello!'

Answer

undefined

Answer

'undefined is not a function'

Question 39

Which of the following is/are strings?

Accepted Answer

'4'

Answer

4

Answer

4.0

Question 40

Which of the following is/are numbers?

Accepted Answer

4

Accepted Answer

4.0

Accepted Answer

-4

Answer

'4'

Question 41

Which of the following is/are booleans?

Accepted Answer

true

Accepted Answer

false

Answer

"true"

Question 42

What is the result of 80 + 71.2?

Accepted Answer

151.2

Answer

151

Answer

8071.2

Question 43

What is the result of "80" + 71.2?

Accepted Answer

"8071.2"

Answer

151.2

Answer

151

Question 44

What is the result of 2 + "2"?

Accepted Answer

"22"

Answer

4

Answer

"4"

Question 45

Does 100 + 30 produce a number or a string?

Accepted Answer

Number

Answer

String

Question 46

Does "100" + 30 produce a number or a string?

Accepted Answer

string

Answer

number

Question 47

Which of the following is the correct way of returning the length of this string?

Accepted Answer

'string'.length

Answer

'string',length

Answer

string,length

Answer

string.length

Question 48

Which of the following will correctly comment the text?

Accepted Answer

// “the text” //

Answer

/ “the text” /

Answer

*/ “the text” /*

Answer

\ “the text” \

Question 49

Which of the following is the correct use of the confirm dialog?

Accepted Answer

confirm(“Hello world”);

Answer

confirm. “Hello world”;

Answer

confirm.(“Hello world”);

Answer

confirm[“Hello world”];

Question 50

Which of the following is the correct way to log a statement to the console?

Accepted Answer

console.log("Hello world")

Answer

consolelog("Hello world")

Answer

console.log{"Hello world"}

Question 51

Which of the following is not a comparator operation in JavaScript?

Accepted Answer

<==

Answer

!==

Answer

===

Answer

>

Question 52

What follows after the expression in an if statement?

Accepted Answer

curly braces

Answer

a colon

Answer

square brackets

Answer

brackets

Question 53

Which of the following statements returns false?

Accepted Answer

'inputControl'.length < 4

Answer

'myName'.length > 2

Answer

3 * 4 < 15

Answer

4 / 2 == 2

Question 54

What is the substring keyword used for?

Accepted Answer

Returning a partial part of a string

Answer

Creating a string within a string

Answer

Reordering characters in a string

Answer

Substituting characters within a string

Question 55

Which of the following best describes what a function in JavaScript is used for?

Accepted Answer

A reusable piece of code that can be called on throughout an application

Answer

A function creates new variables

Answer

A function is used for math formulas

Answer

A function allows for the use of mathematical operators

Question 56

The input in a function is called?

Accepted Answer

parameter

Answer

function variable

Answer

return

Answer

global variable

Question 57

Which of the following demonstrates correct syntax for a function?
//1 var myFunction = function[] {};
//2 var myFunction = function() {};
//3 var myFunction = function{} ();
//4 var myFunction = function(); {};

Accepted Answer

2

Answer

1

Answer

3

Answer

4

Question 58

Which of the following the correct way to call the function below?

var multiplier = function(number) {
  console.log(3 * number);
};

Accepted Answer

multiplier(5);

Answer

multiplier 5 ;

Answer

multiplier{5};

Answer

multiplier[5];

Question 59

Which of the following correctly calls this function?

var input = prompt("Enter input value");
var controlVal = input / 2 + 3;
var multiplier = function(number, phase) {

var val = number *  controlVal + phase;

console.log(val);

};

Accepted Answer

multiplier(2, 1);

Answer

number(2);

Answer

number(2, 1);

Answer

multiplier(2);

Question 60

Which of the following is the end condition for this for loop?
for (var condition = 0; condition < 5; condition ++) {
 return condition;
};

Accepted Answer

condition < 5

Answer

condition = 0

Answer

condition ++

Answer

return condition

Question 61

Which of the following is the start condition for this for loop?
for (var condition = 0; condition < 5; condition ++) {
   return condition;
};

Accepted Answer

condition = 0

Answer

condition ++

Answer

return condition

Answer

condition < 5

Question 62

What best describes the function of a for loop?

Accepted Answer

It loops through a block of code by a determinable amount of loops

Answer

It looks for a loop in a block of code

Answer

It loops through code only within a function

Answer

It loops through a block of code by an undeterminable amount of loops

Question 63

What does this for loop do?
for (var i = 2; i <= 7; i++) {
  console.log(i);
};

Accepted Answer

prints the numbers 2 to 7

Answer

prints i seven times

Answer

prints the numbers 1 to 7

Answer

prints the numbers 2 to 6

Question 64

Which of the following for loops prints the block of code below?

//0 5 10 15 20 25
//Scroll down
//1 for (var i = 1; i <= 25; i+= 5) {
    console.log(i);
};
//2 for (var i = 0; i < 28; i += 5) {
    console.log(i);
};
//3 for (var i = 0; i < 25; i =+ 5) {
    console.log(i);
};
//4 for (var i = 0; i <= 25; i =+ 5) {
    console.log(i);
};

Accepted Answer

2

Answer

1

Answer

3

Answer

4

JavaScript

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