JavaScript-Developer-I Practice Exam Questions and Answers

A developer at Universal Containers is creating their new landing page based on HTML, CSS, and JavaScript. The website includes multiple external resources that are loaded when the page is opened.

To ensure that visitors have a good experience, a script named personalizeWebsiteContent needs to be executed when the webpage is loaded and there is no need to wait for the resources to be available.

Which statement should be used to call personalizeWebsiteContent based on the above business requirement?

Refer to the following code that imports a module named utils:

import (foo, bar) from ‘/path/Utils.js’;

foo() ;

bar() ;

Which two implementations of Utils.js export foo and bar such that the code above runs without

error?

Choose 2 answers

A developer has an is Dog function that takes one argument cat. They want to schedule the function to run every minute.

What is the correct syntax for scheduling this function?

A developer wants to define a function log to be used a few times on a single-file JavaScript script.

01 // Line 1 replacement

02 console.log('"LOG:', logInput);

03 }

Which two options can correctly replace line 01 and declare the function for use?

Choose 2 answers

The developer wants to test the array shown:

const arr = Array(5).fill(0)

Which two tests are the most accurate for this array ?

Choose 2 answers:

Refer to the following code:

What will the console show when the button is clicked?

A developer wants to create an object from a function in the browser using the code

below:

Function Monster() { this.name = ‘hello’ };

Const z = Monster();

What happens due to lack of the new keyword on line 02?

Given the code below:

Setcurrent URL ();

console.log(‘The current URL is: ‘ +url );

function setCurrentUrl() {

Url = window.location.href:

What happens when the code executes?

Which two options are core Node.js modules?

Choose 2 answers

A developer at Universal Containers creates a new landing page based on HTML, CSS, and

JavaScript TO ensure that visitors have a good experience, a script named personaliseContext

needs to be executed when the webpage is fully loaded (HTML content and all related files ), in

order to do some custom initialization.

Which statement should be used to call personalizeWebsiteContent based on the above

business requirement?

A Developer wrote the following code to test a sum3 function that takes in an array of

numbers and returns the sum of the first three number in the array, The test passes:

Let res = sum2([1, 2, 3 ]) ;

console.assert(res === 6 );

Res = sum3([ 1, 2, 3, 4]);

console.assert(res=== 6);

A different developer made changes to the behavior of sum3 to instead sum all of the numbers

present in the array. The test passes:

Which two results occur when running the test on the updated sum3 function ?

Choose 2 answers

A developer has an ErrorHandler module that contains multiple functions.

What kind of export should be leveraged so that multiple functions can be used?

Given the JavaScript below:

Which code should replace the placeholder comment on line 06 to hide accounts that do not match the search string?

A developer creates a simple webpage with an input field. When a user enters text in the input field and clicks the button, the actual value of the field must be displayed in the console.

Here is the HTML file content:

Display The developer wrote the javascript code below:

Const button = document.querySelector(‘button’);

button.addEvenListener(‘click’, () => (

Const input = document.querySelector(‘input’);

console.log(input.getAttribute(‘value’));

When the user clicks the button, the output is always “Hello”.

What needs to be done to make this code work as expected?

A developer wrote the following code to test a sum3 function that takes in an array of numbers and returns the sum of the first three numbers in the array, and the test passes.

A different developer made changes to the behavior of sum3 to instead sum only the first two numbers present in the array.

Which two results occur when running this test on the updated sum3 function?

Choose 2 answers

developer has a web server running with Node.js. The command to start the web

server is node server,js. The web server started having latency issues. Instead of a one second

turn around for web requests, the developer now sees a five second turnaround,

Which command can the web developer run to see what the module is doing during the

latency period?

The developer has a function that prints “Hello” to an input name. To test this, thedeveloper created a function that returns “World”. However the following snippet does not print “ Hello World”.

What can the developer do to change the code to print “Hello World” ?

Refer to the code below:

Let inArray =[ [ 1, 2 ] , [ 3, 4, 5 ] ];

Which two statements result in the array [1, 2, 3, 4, 5] ?

Choose 2 answers

Universal Containers (UC) just launched a new landing page, but users complain that the website is slow. A developer found some functions any that might cause this problem. To verify this, the developer decides to execute everything and log the time each of these three suspicious functions consumes.

Which function can the developer use to obtain the time spent by every one of the three functions?

Refer to HTML below:

The current status of an Order: In Progress

Which JavaScript statement changes the text ‘In Progress’ to ‘Completed’ ?

Given the following code, what is the value of x?

let x = ‘15' + (10 * 2);

A developer wants to leverage a module to print a price in pretty format, and has imported a method as shown below:

Import printPrice from ‘/path/PricePrettyPrint.js’;

Based on the code, what must be true about the printPrice function of the PricePrettyPrint module for this import to work ?

A developer tries to retrieve all cookies, then sets a certain key value pair in the cookie. These statements are used:

What is the behavior?

Refer the following code

what is the value of array after code executes?

A developer wrote a fizzbuzz function that when passed in a number, returns the

following:

● ‘Fizz’ if the number is divisible by 3.

● ‘Buzz’ if the number is divisible by 5.

● ‘Fizzbuzz’ if the number is divisible by both 3 and 5.

● Empty string if the number is divisible by neither 3 or 5.

Which two test cases will properly test scenarios for the fizzbuzz function?

Choose 2 answers

A developer has the following array of student test grades:

Let arr = [ 7, 8, 5, 8, 9 ];

The Teacher wants to double each score and then see an array of the students

who scored more than 15 points.

How should the developer implement the request?

Refer to the string below:

const str = 'Salesforce';

Which two statements result in the word 'Sales'?

Choose 2 answers

At Universal Containers, every team has its own way of copying JavaScript objects. The code snippet shows an Implementation from one team:

What is the output of the code execution?

What are two unique features of functions defined with a fat arrow as compared to normal function definition?

Choose 2 answers

Universal Containers recently launched its new landing page to host a crowd-funding

campaign. The page uses an external library to display some third-party ads. Once the page is

fully loaded, it creates more than 50 new HTML items placed randomly inside the DOM, like the

one in the code below:

All the elements includes the same ad-library-item class, They are hidden by default, and they are randomly displayed while the user navigates through the page.

Refer to the code below:

function foo () {

const a =2;

function bat() {

console.log(a);

}

return bar;

}

Why does the function bar have access to variable a ?

A developer wants to use a module named universalContainersLib and then call functions from it.

How should a developer import every function from the module and then call the functions foo and bar?

A developer creates a class that represents a blog post based on the requirement that a

Post should have a body author and view count.

The Code shown Below:

Class Post {

// Insert code here

This.body =body

This.author = author;

this.viewCount = viewCount;

}

}

Which statement should be inserted in the placeholder on line 02 to allow for a variable to be set

to a new instanceof a Post with the three attributes correctly populated?