1.
`<>`
2.
`~`
3.
`==!`
4.
`!==`
Q 1 / 121
1.
Only a for statement uses a callback function.
2.
A for statement is generic, but a forEach statement can be used only with an array.
3.
Only a forEach statement lets you specify your own iterator.
4.
A forEach statement is generic, but a for statement can be used only with an array.
Q 2 / 121
js function addTax(total) { return total * 1.05; }1.
`addTax = 50;`
2.
`return addTax 50;`
3.
`addTax(50);`
4.
`addTax 50;`
Q 3 / 121
1.
`let rate = 100;`
2.
`let 100 = rate;`
3.
`100 = let rate;`
4.
`rate = 100;`
Q 4 / 121
1.
`var student = new Person();`
2.
`var student = construct Person;`
3.
`var student = Person();`
4.
`var student = construct Person();`
Q 5 / 121
js let modal = document.querySelector('#result'); setTimeout(function(){ modal.classList.remove('hidden); }, 10000); console.log('Results shown');1.
after 10 second
2.
after results are received from the HTTP request
3.
after 10000 seconds
4.
immediately
Q 6 / 121
javascript class Animal { static belly = []; eat() { Animal.belly.push('food'); } } let a = new Animal(); a.eat(); console.log(/* Snippet Here */); //Prints food1.
`a.prototype.belly[0]`
2.
`Object.getPrototype0f (a).belly[0]`
3.
`Animal.belly[0]`
4.
`a.belly[0]`
Q 7 / 121
javascript for (var i = 1; i <= 4; i++) { setTimeout(function () { console.log(i); }, i * 10000); } javascript for (var i = 1; i <= 4; i++) { (function (i) { setTimeout(function () { console.log(j); }, j * 1000); })(j); } javascript while (var i=1; i<=4; i++) { setTimeout(function() { console.log(i); }, i*1000); } javascript for (var i = 1; i <= 4; i++) { (function (j) { setTimeout(function () { console.log(j); }, j * 1000); })(i); } javascript for (var j = 1; j <= 4; j++) { setTimeout(function () { console.log(j); }, j * 1000); } 1. [Reference setTimeout](https://developer.mozilla.org/en-US/docs/Web/API/setTimeout) 2. [Reference immediately invoked anonymous functions](https://www.javascripttutorial.net/javascript-anonymous-functions/)1.
javascript
for (var i = 1; i <= 4; i++) {
(function (i) {
setTimeout(function () {
console.log(j);
}, j * 1000);
})(j);
}
2.
javascript
while (var i=1; i<=4; i++) {
setTimeout(function() {
console.log(i);
}, i*1000);
}
3.
javascript
for (var i = 1; i <= 4; i++) {
(function (j) {
setTimeout(function () {
console.log(j);
}, j * 1000);
})(i);
}
4.
javascript
for (var j = 1; j <= 4; j++) {
setTimeout(function () {
console.log(j);
}, j * 1000);
}
Q 8 / 121
1.
It reloads the document whenever the value changes.
2.
It returns a reference to a variable in its parent scope.
3.
It completes execution without returning.
4.
It copies a local variable to the global scope.
Q 9 / 121
js let discountPrice = function (price) { return price * 0.85; }; js let discountPrice(price) { return price * 0.85; }; js let function = discountPrice(price) { return price * 0.85; }; js discountPrice = function (price) { return price * 0.85; };1.
js
let discountPrice = function (price) {
return price * 0.85;
};
2.
js
let discountPrice(price) {
return price * 0.85;
};
3.
js
let function = discountPrice(price) {
return price * 0.85;
};
4.
js
discountPrice = function (price) {
return price * 0.85;
};
Q 10 / 121
js var Storm = function () {}; Storm.prototype.precip = 'rain'; var WinterStorm = function () {}; WinterStorm.prototype = new Storm(); WinterStorm.prototype.precip = 'snow'; var bob = new WinterStorm(); console.log(bob.precip);1.
Storm()
2.
undefined
3.
'rain'
4.
'snow'
Q 11 / 121
NOTE: The first three are all partially correct and will match digits, but the **second option is the most correct** because it will **only** match **2 digit** time values (12:00:32). The first option would have worked if the repitions range looked like `[0-9]{2}`, however because of the **comma** `[0-9]{2,}` it will select 2 **or more** digits (120:000:321). The third option will any range of time digits, single _and_ multiple (meaning `1:2:3` will also match). **More resources:** 1. [Repeating characters](https://regexone.com/lesson/repeating_characters) 2. [Kleene operators](https://regexone.com/lesson/kleene_operators)1.
`/[0-9]{2,}:[0-9]{2,}:[0-9]{2,}/`
2.
`/dd:dd:dd/`
3.
`/[0-9]+:[0-9]+:[0-9]+/`
4.
`/ : : /`
Q 12 / 121
js 'use strict'; function logThis() { this.desc = 'logger'; console.log(this); } new logThis();1.
`undefined`
2.
`window`
3.
`{desc: "logger"}`
4.
`function`
Q 13 / 121
js let roadTypes = ['street', 'road', 'avenue', 'circle'];1.
roadTypes.2
2.
roadTypes[3]
3.
roadTypes.3
4.
roadTypes[2]
Q 14 / 121
javascript console.log(typeof 42);1.
`'float'`
2.
`'value'`
3.
`'number'`
4.
`'integer'`
Q 15 / 121
1.
`self`
2.
`object`
3.
`target`
4.
`source`
Q 16 / 121
js function addNumbers(x, y) { if (isNaN(x) || isNaN(y)) { } }1.
`exception('One or both parameters are not numbers')`
2.
`catch('One or both parameters are not numbers')`
3.
`error('One or both parameters are not numbers')`
4.
`throw('One or both parameters are not numbers')`
Q 17 / 121
1.
`JSON.fromString();`
2.
`JSON.parse()`
3.
`JSON.toObject()`
4.
`JSON.stringify()`
Q 18 / 121
1.
When you want to reuse a set of statements multiple times.
2.
When you want your code to choose between multiple options.
3.
When you want to group data together.
4.
When you want to loop through a group of statement.
Q 19 / 121
js for (var i = 0; i < 5; i++) { console.log(i); }1.
12345
2.
1234
3.
01234
4.
012345
Q 20 / 121
1.
`Object.get()`
2.
`Object.loop()`
3.
`Object.each()`
4.
`Object.keys()`
Q 21 / 121
js var a = ['dog', 'cat', 'hen']; a[100] = 'fox'; console.log(a.length);1.
101
2.
3
3.
4
4.
100
Q 22 / 121
**Explanation:** `Map.prototype.size returns the number of elements in a Map, whereas Object does not have a built-in method to return its size.`1.
You can iterate over values in a Map in their insertion order.
2.
You can count the records in a Map with a single method call.
3.
Keys in Maps can be strings.
4.
You can access values in a Map without iterating over the whole collection.
Q 23 / 121
js const dessert = { type: 'pie' }; dessert.type = 'pudding';1.
pie
2.
The code will throw an error.
3.
pudding
4.
undefined
Q 24 / 121
1.
ReferenceError
2.
True
3.
0
4.
false
Q 25 / 121
1.
`++`
2.
`--`
3.
`==`
4.
`||`
Q 26 / 121
1.
`Student.parent = Person;`
2.
`Student.prototype = new Person();`
3.
`Student.prototype = Person;`
4.
`Student.prototype = Person();`
Q 27 / 121
1.
to tell parsers to interpret your JavaScript syntax loosely
2.
to tell parsers to enforce all JavaScript syntax rules when processing your code
3.
to instruct the browser to automatically fix any errors it finds in the code
4.
to enable ES6 features in your code
Q 28 / 121
1.
all of them
2.
`const`
3.
`var`
4.
`let`
Q 29 / 121
1.
`Boolean(0)`
2.
`Boolean("")`
3.
`Boolean(NaN)`
4.
`Boolean("false")`
Q 30 / 121
1.
`this`
2.
`catch`
3.
`function`
4.
`array`
Q 31 / 121
1.
Arguments
2.
args
3.
argsArray
4.
argumentsList
Q 32 / 121
js class X { get Y() { return 42; } } var x = new X();1.
`x.get('Y')`
2.
`x.Y`
3.
`x.Y()`
4.
`x.get().Y`
Q 33 / 121
js sum(10, 20); diff(10, 20); function sum(x, y) { return x + y; } let diff = function (x, y) { return x - y; };1.
30, ReferenceError, 30, -10
2.
30, ReferenceError
3.
30, -10
4.
ReferenceError, -10
Q 34 / 121
**Explanation:** Records in an object can be retrieved using their key which can be any given value (e.g. an employee ID, a city name, etc), whereas to retrieve a record from an array we need to know its index.1.
Objects are more efficient in terms of storage.
2.
Adding a record to an object is significantly faster than pushing a record into an array.
3.
Most operations involve looking up a record, and objects can do that better than arrays.
4.
Working with objects makes the code more readable.
Q 35 / 121
1.
It can be used for both internal and external JavaScript code.
2.
It can be used only for internal JavaScript code.
3.
It can be used only for internal or external JavaScript code that exports a promise.
4.
It can be used only for external JavaScript code.
Q 36 / 121
1.
`import _ from 'lodash';`
2.
`import 'lodash' as _;`
3.
`import '_' from 'lodash;`
4.
`import lodash as _ from 'lodash';`
Q 37 / 121
js1.
True
2.
undefined
3.
[]
4.
False
Q 38 / 121
1.
Generator function
2.
Arrow function
3.
Async/ Await function
4.
Promise function
Q 39 / 121
js var v = 1; var f1 = function () { console.log(v); }; var f2 = function () { var v = 2; f1(); }; f2();1.
2
2.
1
3.
Nothing - this code will throw an error.
4.
undefined
Q 40 / 121
1.
Every object in the program has to be a function.
2.
Code is grouped with the state it modifies.
3.
Date fields and methods are kept in units.
4.
Side effects are not allowed.
Q 41 / 121
**Explanation**: `You cannot invoke reduce on undefined object... It will throw (yourObject is not Defined...)`1.
You are calling a method named reduce on an object that's declared but has no value.
2.
You are calling a method named reduce on an object that does not exist.
3.
You are calling a method named reduce on an empty array.
4.
You are calling a method named reduce on an object that's has a null value.
Q 42 / 121
`let arr = [];`1.
3
2.
2
3.
0
4.
1
Q 43 / 121
1.
`typeof`
2.
`delete`
3.
`instanceof`
4.
`void`
Q 44 / 121
javascript var start = 1; if (start === 1) { let end = 2; }1.
conditional
2.
block
3.
global
4.
function
Q 45 / 121
js const x = 6 % 2; const y = x ? 'One' : 'Two';1.
One
2.
undefined
3.
TRUE
4.
Two
Q 46 / 121
1.
`throw`
2.
`exception`
3.
`catch`
4.
`error`
Q 47 / 121
1.
The defer attribute can work synchronously.
2.
The defer attribute works only with generators.
3.
The defer attribute works only with promises.
4.
The defer attribute will asynchronously load the scripts in order.
Q 48 / 121
js var a; var b = (a = 3) ? true : false;1.
The condition in the ternary is using the assignment operator.
2.
You can't define a variable without initializing it.
3.
You can't use a ternary in the right-hand side of an assignment operator.
4.
The code is using the deprecated var keyword.
Q 49 / 121
html <p class="pull">lorem ipsum</p>1.
`Document.querySelector('class.pull')`
2.
`document.querySelector('.pull');`
3.
`Document.querySelector('pull')`
4.
`Document.querySelector('#pull')`
Q 50 / 121
js let answer = true; if (answer === false) { return 0; } else { return 10; }1.
10
2.
true
3.
false
4.
0
Q 51 / 121
js var start = 1; function setEnd() { var end = 10; } setEnd(); console.log(end);1.
10
2.
0
3.
ReferenceError
4.
undefined
Q 52 / 121
js function sayHello() { console.log('hello'); } console.log(sayHello.prototype);1.
undefined
2.
"hello"
3.
an object with a constructor property
4.
an error message
Q 53 / 121
1.
Object
2.
Set
3.
Array
4.
Map
Q 54 / 121
js function printA() { console.log(answer); var answer = 1; } printA(); printA();1.
`1` then `1`
2.
`1` then `undefined`
3.
`undefined` then `undefined`
4.
`undefined` then `1`
Q 55 / 121
1.
forEach allows you to specify your own iterator, whereas for does not.
2.
forEach can be used only with strings, whereas for can be used with additional data types.
3.
forEach can be used only with an array, whereas for can be used with additional data types.
4.
for loops can be nested; whereas forEach loops cannot.
Q 56 / 121
1.
=> `({})`
2.
=> `{}`
3.
=> `{ return {};}`
4.
=> `(({}))`
Q 57 / 121
**EXPLANATION:** "to ensure that tasks further down in your code are not initiated until earlier tasks have completed" you use the normal (synchronous) flow where each command is executed sequentially. Asynchronous code allows you to break this sequence: start a long running function (AJAX call to an external service) and continue running the rest of the code in parallel.1.
to start tasks that might take some time without blocking subsequent tasks from executing immediately
2.
to ensure that tasks further down in your code are not initiated until earlier tasks have completed
3.
to make your code faster
4.
to ensure that the call stack maintains a LIFO (Last in, First Out) structure
Q 58 / 121
1.
`[3
2.
`3 == '3'`
3.
`3 != '3'`
4.
`3 === '3'`
Q 59 / 121
1.
5thItem
2.
firstName
3.
grand total
4.
function
Q 60 / 121
1.
`cancel()`
2.
`stop()`
3.
`preventDefault()`
4.
`prevent()`
Q 61 / 121
1.
`attachNode()`
2.
`getNode()`
3.
`querySelector()`
4.
`appendChild()`
Q 62 / 121
1.
`break`
2.
`pass`
3.
`skip`
4.
`continue`
Q 63 / 121
1.
`(a,b) => c`
2.
`a, b => {return c;}`
3.
`a, b => c`
4.
`{ a, b } => c`
Q 64 / 121
1.
class
2.
generator function
3.
map
4.
proxy
Q 65 / 121
1.
`! This is a comment`
2.
`# This is a comment`
3.
` This is a comment`
4.
`// This is a comment`
Q 66 / 121
1.
TypeError
2.
SystemError
3.
SyntaxError
4.
LogicError
Q 67 / 121
1.
create()
2.
new()
3.
constructor()
4.
init()
Q 68 / 121
javascript let a = 5; console.log(++a);1.
4
2.
10
3.
6
4.
5
Q 69 / 121
javascript button.addEventListener( 'click', function (e) { button.className = 'clicked'; }, false, );1.
`e.blockReload();`
2.
`button.preventDefault();`
3.
`button.blockReload();`
4.
`e.preventDefault();`
Q 70 / 121
1.
`function() { console.log('lorem ipsum'); }()();`
2.
`function() { console.log('lorem ipsum'); }();`
3.
`(function() { console.log('lorem ipsum'); })();`
Q 71 / 121
1.
`Document.querySelector('img')`
2.
`Document.querySelectorAll('<img>')`
3.
`Document.querySelectorAll('img')`
4.
`Document.querySelector('<img>')`
Q 72 / 121
1.
To use ES6 syntax
2.
To start tasks that might take some time without blocking subsequent tasks from executing immediately
3.
To ensure that parsers enforce all JavaScript syntax rules when processing your code
4.
To ensure that tasks further down in your code aren't initiated until earlier tasks have completed
Q 73 / 121
1.
DELETE
2.
GET
3.
PATCH
4.
POST
Q 74 / 121
1.
focus
2.
blur
3.
hover
4.
enter
Q 75 / 121
javascript function logThis() { console.log(this); } logThis();1.
function
2.
undefined
3.
Function.prototype
4.
window
Q 76 / 121
javascript const Greeting = ({ name }) => <h1>Hello {name}!</h1>;1.
`class Greeting extends React.Component { render() { return <h1>Hello {this.props.name}!</h1>; } }`
2.
`class Greeting extends React.Component { constructor() { return <h1>Hello {this.props.name}!</h1>; } }`
3.
`class Greeting extends React.Component { <h>Hello {this.props.name}!</h>; } }`
4.
`class Greeting extends React.Component { render({ name }) { return <h1>Hello {name}!</h1>; } }`
Q 77 / 121
javascript useEffect(() => { // do things }, []);1.
componentWillUnmount
2.
componentDidUpdate
3.
render
4.
componentDidMount
Q 78 / 121
javascript var obj; console.log(obj);1.
`ReferenceError: obj is not defined`
2.
`{}`
3.
`undefined`
4.
`null`
Q 79 / 121
javascript class TaxCalculator { static calculate(total) { return total * 0.05; } }1.
calculate(50);
2.
new TaxCalculator().calculate($50);
3.
TaxCalculator.calculate(50);
4.
new TaxCalculator().calculate(50);
Q 80 / 121
js const foo = { bar() { console.log('Hello, world!'); }, name: 'Albert', age: 26, }; 1. [Reference functions in javascript](https://www.w3schools.com/js/js_functions.asp) 2. [Reference working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects)1.
The function bar needs to be defined as a key/value pair.
2.
Trailing commas are not allowed in JavaScript.
3.
Functions cannot be declared as properties of objects.
4.
Nothing, there are no errors.
Q 81 / 121
js console.log('I'); setTimeout(() => { console.log('love'); }, 0); console.log('Javascript!'); I Javascript! love love I Javascript! I love Javascript!1.
I
Javascript!
love
2.
love
I
Javascript!
3.
I
love
Javascript!
Q 82 / 121
js const foo = [1, 2, 3]; const [n] = foo; console.log(n);1.
1
2.
undefined
3.
NaN
4.
Nothing--this is not proper JavaScript syntax and will throw an error.
Q 83 / 121
js const foo = { name: 'Albert', };1.
delete name from foo;
2.
delete foo.name;
3.
del foo.name;
4.
remove foo.name;
Q 84 / 121
1. [Reference map](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map) 2. [Reference Differences between forEach and for loop](https://www.geeksforgeeks.org/difference-between-foreach-and-for-loop-in-javascript/)1.
There is no difference.
2.
The `forEach()` method returns a single output value, wheras the `map()` method performs operation on each value in the array.
3.
The map() methods returns a new array with a transformation applied on each item in the original array, wheras the `forEach()` method iterates through an array with noreturn value.
4.
The `forEach()` methods returns a new array with a transformation applied on each item in the original array, wheras the `map()` method iterates through an array with noreturn value.
Q 85 / 121
js function makeAdder(x) { return function (y) { return x + y; }; } var addFive = makeAdder(5); console.log(addFive(3));1.
overloading
2.
closure
3.
currying
4.
overriding
Q 86 / 121
1.
`<script></script>`
2.
`<js></js>`
3.
`<javascript></javascript>`
4.
`<code></code>`
Q 87 / 121
js for (var i = 0; i < 5; i++) { console.log(i); }1.
0 1 2 3 4
2.
0 1 2 3 4 5
3.
1 2 3 4
4.
1 2 3 4 5
Q 88 / 121
js const dessert = { type: 'pie' }; dessert.type = 'pudding'; const seconds = dessert; seconds.type = 'fruit'; **Explanation:** `Assigning a variable (such as seconds) to an object (such as dessert) does not create a new object. The seconds variable merely becomes a reference for the dessert object. Any changes made to seconds will also reflect in dessert.`1.
pie
2.
fruit
3.
undefined
4.
pudding
Q 89 / 121
1.
Security-Mode
2.
Access-Control-Allow-Origin
3.
Different-Origin
4.
Same-Origin
Q 90 / 121
js 'use strict'; function logThis() { this.desc = 'logger'; console.log(this); } new logThis();1.
window
2.
undefined
3.
function
4.
{desc: "logger"}
Q 91 / 121
**Explanation:** If the defer attribute is set, it specifies that the script is downloaded in parallel to parsing the page, and executed after the page has finished parsing. [HTML <script> defer Attribute](https://www.w3schools.com/tags/att_script_defer.asp)1.
defer causes the script ta be loaded from the backup content delivery network (CDN).
2.
defer allows the browser ta continue processing the page while the script loads in the background.
3.
defer blacks the browser from processing HTML below the tag until the script is completely loaded.
4.
defer lazy loads the script, causing it to download only when it is called by another script on the page.
Q 92 / 121
js let rainForests = ['Amazon', 'Borneo', 'Cerrado', 'Congo']; rainForests.splice(0, 2); console.log(rainForests);1.
`["Amazon","Borneo","Cerrado","Congo"]`
2.
`["Cerrado", "Congo"]`
3.
`["Congo"]`
4.
`["Amazon","Borneo"]`
Q 93 / 121
js const numbers = [1, 2, 3, 4, 5]; //MISSING LINE1.
`const [one,two,three,four,five]=numbers`
2.
`const {one,two,three,four,five}=numbers`
3.
`const [one,two,three,four,five]=[numbers]`
4.
`const {one,two,three,four,five}={numbers}`
Q 94 / 121
js const obj = { a: 1, b: 2, c: 3, }; const obj2 = { ...obj, a: 0, }; console.log(obj2.a, obj2.b); ### Q96. Which line could you add to this code to print "jaguar" to the console? js let animals = ['jaguar', 'eagle']; //Missing Line console.log(animals.pop()); //Prints jaguar1.
Nothing, it will throw an error
2.
0 2
3.
undefined 2
4.
undefined 2
5.
`animals.filter(e => e === "jaguar");`
6.
`animals.reverse();`
7.
`animals.shift();`
8.
`animals.pop();`
Q 95 / 121
js //Missing Line for (var i = 0; i < vowels.length; i++) { console.log(vowels[i]); //Each letter printed on a separate line as follows; //a //e //i //o //u }1.
`let vowels = "aeiou".toArray();`
2.
`let vowels = Array.of("aeiou");`
3.
`let vowels = {"a", "e", "i", "o", "u"};`
4.
`let vowels = "aeiou";`
Q 96 / 121
js const x = 6 % 2; const y = x ? 'One' : 'Two'; console.log(y);1.
undefined
2.
One
3.
true
4.
Two
Q 97 / 121
`let matrix = [["You","Can"],["Do","It"],["!","!","!"]];`1.
`matrix[1[2]]`
2.
`matrix[1][1]`
3.
`matrix[1,2]`
4.
`matrix[1][2]`
Q 98 / 121
js const animals = ['Rabbit', 'Dog', 'Cat']; animals.unshift('Lizard');1.
It adds "Lizard" to the start of the animals array.
2.
It adds "Lizard" to the end of the animals array.
3.
It replaces "Rabbit" with "Lizard" in the animals array.
4.
It replaces "Cat" with "Lizard" in the animals array.
Q 99 / 121
js let x = 6 + 3 + '3'; console.log(x);1.
93
2.
12
3.
66
4.
633
Q 100 / 121
### Q103. Which statement prints "roar" to the console? js var sound = 'grunt'; var bear = { sound: 'roar', }; function roar() { console.log(this.sound); } 1. [Reference Apply](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/apply) 2. [Reference this](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this) 3. [Reference bind](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_objects/Function/bind)1.
else
2.
when
3.
if
4.
switch
5.
`bear.bind(roar);`
6.
`roar.bind(bear);`
7.
`roar.apply(bear);`
8.
`bear[roar]();`
Q 101 / 121
1.
`a, b => { return c; }`
2.
`a, b => c`
3.
`{ a, b } => c`
4.
`(a,b) => c`
Q 102 / 121
javascript var flagsJSON = '{ "countries" : [' + '{ "country":"Ireland" , "flag":"🇮🇪" },' + '{ "country":"Serbia" , "flag":"🇷🇸" },' + '{ "country":"Peru" , "flag":"🇵🇪" } ]}'; var flagDatabase = JSON.parse(flagsJSON);1.
flagDatabase.countries[0].flag
2.
flagDatabase.countries[1].flag
3.
flagsJSON.countries[0].flag
4.
flagDatabase[1].flag
Q 103 / 121
js //some-file.js export const printMe = (str) => console.log(str);1.
`import printMe from './some-file';`
2.
`import { printMe } from './some-file';`
3.
`import default as printMe from './some-file';`
4.
`const printMe = import './some-file';`
Q 104 / 121
js const arr1 = [2, 4, 6]; const arr2 = [3, 5, 7]; console.log([...arr1, ...arr2]);1.
`[2, 3, 4, 5, 6, 7]`
2.
`[3,5,7,2,4,6]`
3.
`[3, 5, 7, 2, 4, 6]`
4.
`[[2, 4, 6], [3, 5, 7]]`
5.
`[2, 4, 6, 3, 5, 7]`
Q 105 / 121
1.
`done()`
2.
`then()`
3.
`finally()`
4.
`catch()`
Q 106 / 121
1.
`array.slice()`
2.
`array.shift()`
3.
`array.push()`
4.
`array.replace()`
Q 107 / 121
1.
do…while
2.
forEach
3.
while
4.
for
Q 108 / 121
javascript console.log(typeof 'blueberry');1.
`string`
2.
`array`
3.
`Boolean`
4.
`object`
Q 109 / 121
html //HTML Markup <div id="A"> <div id="B"> <div id="C">Click Here</div> </div> </div> javascript //JavaScript document.querySelectorAll('div').forEach((e) => { e.onclick = (e) => console.log(e.currentTarget.id); }); 1. [Reference query selector](https://developer.mozilla.org/en-US/docs/Web/API/Document/querySelector) 2. [Reference events](https://developer.mozilla.org/en-US/docs/Web/Events)1.
C B A
2.
A
3.
C
4.
A B C
Q 110 / 121
js const myNumbers = [1, 2, 3, 4, 5, 6, 7]; const myFunction = (arr) => { return arr.map((x) => x + 3).filter((x) => x < 7); }; console.log(myFunction(myNumbers));1.
[4,5,6,7,8,9,10]
2.
[4,5,6,7]
3.
[1,2,3,4,5,6]
4.
[4,5,6]
Q 111 / 121
js let rainForestAcres = 10; let animals = 0; while (rainForestAcres < 13 || animals <= 2) { rainForestAcres++; animals += 2; } console.log(animals);1.
2
2.
4
3.
6
4.
8
Q 112 / 121
js let cipherText = [...'YZOGUT QGMORTZ MTRHTILS']; let plainText = ''; /* Missing Snippet */ console.log(plainText); //Prints YOU GOT THIS js for (let key of cipherText.keys()) { plainText += key % 2 === 0 ? key : ' '; } js for (let [index, value] of cipherText.entries()) { plainText += index % 2 !== 0 ? value : ''; } js for (let [index, value] of cipherText.entries()) { plainText += index % 2 === 0 ? value : ''; } js for (let value of cipherText) { plainText += value; } 1. [Reference MDN JavaScript Destructuring](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment) 2. [Reference MDN JavaScript Array entries](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/entries) 3. [Reference MDN JavaScript Remainder/Modulo](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Remainder)1.
js
for (let key of cipherText.keys()) {
plainText += key % 2 === 0 ? key : ' ';
}
2.
js
for (let [index, value] of cipherText.entries()) {
plainText += index % 2 !== 0 ? value : '';
}
3.
js
for (let [index, value] of cipherText.entries()) {
plainText += index % 2 === 0 ? value : '';
}
4.
js
for (let value of cipherText) {
plainText += value;
}
Q 113 / 121
js const foo = [1, 2, 3]; const [n] = foo; console.log(n);1.
undefined
2.
1
3.
NaN
4.
Nothing. This is not proper JavaScript syntax and will throw an error.
Q 114 / 121
js var pokedex = ['Snorlax', 'Jigglypuff', 'Charmander', 'Squirtle']; pokedex.pop(); console.log(pokedex.pop()); `The pop() method removes the last element from an array and returns that element. This method changes the length of the array.` [(Source)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/pop)1.
Charmander
2.
Jigglypuff
3.
Snorlax
4.
Squirtle
Q 115 / 121
js let conservation = true; let deforestation = false; let acresOfRainForest = 100; if(/* Snippet goes here */){ ++acresOfRainForest; }1.
`!deforestation && !conservation`
2.
`deforestation && conservation || deforestation`
3.
`conservation && !deforestation`
4.
`!conservation || deforestation`
Q 116 / 121
html <h1 class="content">LinkedIn Learning</h1> <div class="content"> <span class="content">The LinkedIn Learning library has great JavaScript courses!</span> </div>1.
document.querySelector("div.content")
2.
document.querySelector("span.content")
3.
document.querySelector(".content")
4.
document.querySelector("div.span")
Q 117 / 121
1.
`[]`
2.
`undefined`
3.
`0`
4.
`null`
Q 118 / 121
js const lion = 1; let tiger = 2; var bear; ++lion; bear += lion + tiger; tiger++; 1. [const - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/const) 2. [TypeError: invalid assignment to const "x" - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_const_assignment)1.
`line 5, because lion cannot be reassigned a value`
2.
`line 6, because the += operator cannot be used with the undefined variable bear`
3.
`line 5, because the prefix (++) operator does not exist in JavaScript`
4.
`line 3, because the variable bear is left undefined`
Q 119 / 121
js const person = { name: 'Dave', age: 40, hairColor: 'blue' }; const result = Object.keys(person).map((x) => x.toUpperCase()); 1. [Object.keys() - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys) 2. [Array.prototype.map() - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map) 3. [String.prototype.toUpperCase() - JavaScript | MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase)1.
It will throw a TypeError.
2.
`["Name", "Age", "HairColor"]`
3.
`["DAVE", 40, "BLUE"]`
4.
`["NAME", "AGE", "HAIRCOLOR"]`
Q 120 / 121
js console.log('I'); setTimeout(() => { console.log('love'); }, 0); console.log('JavaScript!'); txt I love JavaScript! txt I JavaScript! love txt love I JavaScript!1.
txt
I
love
JavaScript!
2.
txt
I
JavaScript!
love
3.
txt
love
I
JavaScript!
Q 121 / 121