EMT Practice Test

1. Question Content...

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Question1: Which code statement correctly retrieves and returns an object from localStorage?

Question2: Given the code below:
const copy = JSON.stringify([ new String(' false '), new Bollean( false ), undefined ]); What is the value of copy?

Question3: GIven a value, which three options can a developer use to detect if the value is NaN?
Choose 3 answers !

Question4: developer creates a new web server that uses Node.js. It imports a server library that uses events and callbacks for handling server functionality.
The server library is imported with require and is made available to the code by a variable named server. The developer wants to log any issues that the server has while booting up.
Given the code and the information the developer has, which code logs an error at boost with an event?

Question5: developer uses the code below to format a date.

After executing, what is the value of formattedDate?

Question6: Refer to the HTML below:
<div id="main">
<ul>
<li>Leo</li>
<li>Tony</li>
<li>Tiger</li>
</ul>
</div>
Which JavaScript statement results in changing " Tony" to "Mr. T."?

Question7: A developer writes the code below to return a message to a user attempting to register a new username. If the username is available, a variable named nag is declared and assigned a value on line 03.

What is the value of msg when getAvailableabilityMessage ("newUserName") is executed and get Availability ("newUserName") returns true?

Question8: Refer to the code below:

What is the value of result when the code executes?

Question9: Given the following code, what is the value of x?
let x = '15' + (10 * 2);

Question10: Given two expressions var1 and var2. What are two valid ways to return the logical AND of the two expressions and ensure it is data type Boolean ?
Choose 2 answers:

Question11: At Universal Containers, every team has its own way of copying JavaScript objects. The code Snippet shows an implementation from one team:
Function Person() {
this.firstName = "John";
this.lastName = 'Doe';
This.name =() => (
console.log('Hello $(this.firstName) $(this.firstName)');
)}
Const john = new Person ();
Const dan = JSON.parse(JSON.stringify(john));
dan.firstName ='Dan';
dan.name();
What is the Output of the code execution?

Question12: Refer to the following code:
01 function Tiger(){
02 this.Type = 'Cat';
03 this.size = 'large';
04 }
05
06 let tony = new Tiger();
07 tony.roar = () =>{
08 console.log('They\'re great1');
09 };
10
11 function Lion(){
12 this.type = 'Cat';
13 this.size = 'large';
14 }
15
16 let leo = new Lion();
17 //Insert code here
18 leo.roar();
Which two statements could be inserted at line 17 to enable the function call on line 18?
Choose 2 answers.

Question13: Refer to the code below:
01 const server = require('server');
02 /* Insert code here */
A developer imports a library that creates a web server. The imported library uses events and callbacks to start the servers Which code should be inserted at the line 03 to set up an event and start the web server ?

Question14: A developer has the function, shown below, that is called when a page loads.
function onload() {
console.log("Page has loaded!");
}
Where can the developer see the log statement after loading the page in the browser?

Question15: Universal Containers (UC) notices that its application that allows users to search for accounts makes a network request each time a key is pressed. This results in too many requests for the server to handle.
* Address this problem, UC decides to implement a debounce function on string change handler.
What are three key steps to implement this debounce function?
Choose 3 answers:

Question16: Refer to the code declarations below:

Which three expressions return the string JavaScript?
Choose 3 answers

Question17: Which statement accurately describes the behaviour of the async/ await keyworks ?

Question18: 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 ?

Question19: Which two console logs outputs NaN ?
Choose 2 answers

Question20: A developer creates a generic function to log custom messages in the console. To do this, the function below is implemented.
01 function logStatus(status){
02 console./*Answer goes here*/{'Item status is: %s', status};
03 }
Which three console logging methods allow the use of string substitution in line 02?

Question21: Cloud Kicks has a class to represent items for sale in an online store, as shown below:
Class Item{
constructor (name, price){
this.name = name;
this.price = price;
}
formattedPrice(){
return 's' + String(this.price);}}
A new business requirement comes in that requests a ClothingItem class that should have all of the properties and methods of the Item class but will also have properties that are specific to clothes.
Which line of code properly declares the clothingItem class such that it inherits from Item?

Question22: Given the HTML below:

Which statement adds the priority-account css class to the Applied Shipping row?

Question23: Given the following code:

What will be the first four numbers logged?

Question24: 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?

Question25: A developer has the following array of hourly wages:
Let arr = (8, 5, 9, 75, 11, 25, 7, 75, , 13, 25);
For workers making less than $10 an hour rate should be multiple by 1.25 and returned in a new array.
How should the developer implement the request?

Question26: Refer to code below:
console.log(0);
setTimeout(() => (
console.log(1);
});
console.log(2);
setTimeout(() => {
console.log(3);
), 0);
console.log(4);
In which sequence will the numbers be logged?

Question27: 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

Question28: Given the following code:

What is the output of line 02?

Question29: A developer writers the code below to calculate the factorial of a given number.
Function factorial(number) {
Return number + factorial(number -1);
}
factorial(3);
What is the result of executing line 04?

Question30: 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?

Question31: What are two unique features of functions defined with a fat arrow as compared to normal function definition?
Choose 2 answers

Question32: Considering type coercion, what does the following expression evaluate to?
True + '13' + NaN

Question33: Refer to the code below:

Line 05 causes an error.
What are the values of greeting and salutation once code completes?

Question34: Refer to the code below:
let timeFunction =() => {
console.log('Timer called.");
};
let timerId = setTimeout (timedFunction, 1000);
Which statement allows a developer to cancel the scheduled timed function?

Question35: Refer to the code below:
Async funct on functionUnderTest(isOK) {
If (isOK) return 'OK' ;
Throw new Error('not OK');
)
Which assertion accuretely tests the above code?

Question36: 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

Question37: Refer to the following code:
Let sampleText = 'The quick brown fox jumps';
A developer needs to determine if a certain substring is part of a string.
Which three expressions return true for the given substring ?
Choose 3 answers

Question38: R74
new Promise((resolve, reject) => {
const fraction = Math.random();
if( fraction >0.5) reject("fraction > 0.5, " + fraction);
resolve(fraction);
})
.then(() =>console.log("resolved"))
.catch((error) => console.error(error))
.finally(() => console.log(" when am I called?"));

When does Promise.finally on line 08 get called?

Question39: 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:
<input type =" text" value="Hello" name ="input">
<button type ="button" >Display </button>
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 make this code work as expected?

Question40: Given the expressions var1 and var2, what are two valid ways to return the concatenation of the two expressions and ensure it is string? Choose 2 answers

Question41: Refer to the code below:
for(let number =2 ; number <= 5 ; number += 1 ) {
// insert code statement here
}
The developer needs to insert a code statement in the location shown. The code statement has these requirements:
1. Does require an import
2. Logs an error when the boolean statement evaluates to false
3. Works in both the browser and Node.js
Which meet the requirements?

Question42: developer removes the HTML class attribute from the checkout button, so now it is simply:
<button>Checkout</button>.
There is a test to verify the existence of the checkout button, however it looks for a button with class= "blue". The test fails because no such button is found.
Which type of test category describes this test?

Question43: Refer to the code below:
Const pi = 3.1415326,
What is the data type of pi?

Question44: What is the result of the code block?

Question45: Refer to HTML below:
<p> The current status of an Order: <span id ="status"> In Progress </span> </p>.
Which JavaScript statement changes the text 'In Progress' to 'Completed' ?

Question46: Refer to code below:
Let first = 'who';
Let second = 'what';
Try{
Try{
Throw new error('Sad trombone');
}catch (err){
First ='Why';
}finally {
Second ='when';
} catch (err) {
Second ='Where';
}
What are the values for first and second once the code executes ?

Question47: Refer to the code snippet:
Function getAvailabilityMessage(item) {
If (getAvailability(item)){
Var msg ="Username available";
}
Return msg;
}
A developer writes this code to return a message to user attempting to register a new username. If the username is available, variable.
What is the return value of msg hen getAvailabilityMessage ("newUserName" ) is executed and getAvailability("newUserName") returns false?

Question48: A developer has a formatName function that takes two arguments, firstName and lastName and returns a string. They want to schedule the function to run once after five seconds.
What is the correct syntax to schedule this function?

Question49: Refer to the code below:

What is the output of this function when called with an empty array?

Question50: Given the code below:
01 function GameConsole (name) {
02 this.name = name;
03 }
04
05 GameConsole.prototype.load = function(gamename) {
06 console.log( ` $(this.name) is loading a game : $(gamename) ...`);
07 )
08 function Console 16 Bit (name) {
09 GameConsole.call(this, name) ;
10 }
11 Console16bit.prototype = Object.create ( GameConsole.prototype) ;
12 //insert code here
13 console.log( ` $(this.name) is loading a cartridge game : $(gamename) ...`);
14 }
15 const console16bit = new Console16bit(' SNEGeneziz ');
16 console16bit.load(' Super Nonic 3x Force ');
What should a developer insert at line 15 to output the following message using the method ?
> SNEGeneziz is loading a cartridge game: Super Monic 3x Force . . .

Question51: Given the code below:
Which three code segments result in a correct conversion from number to string? Choose 3 answers

Question52: Which code change should be done for the console to log the following when 'Click me!' is clicked'
> Row log
> Table log

Question53: 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

Question54: Refer to the code below:
let car1 = new Promise((_ ,reject)=> setTimeout(reject,2000,"Car1 crashed in")); let car2 = new Promise(resolve => setTimeout(resolve,1500,"Car2 completed")); let car3 = new Promise(resolve => setTimeout(resolve,3000,"Car3 completed")); Promise.race([car1,car2,car3])
.then(value=>{
let result = `${value} the race.`;
}).catch(err=>{
console.log('Race is cancelled.',err);
});
What is the value of result when promise.race execues?

Question55: Which three options show valid methods for creating a fat arrow function?
Choose 3 answers

Question56: developer is trying to convince management that their team will benefit from using Node.js for a backend server that they are going to create. The server will be a web server that handles API requests from a website that the team has already built using HTML, CSS, and JavaScript.
Which three benefits of Node.js can the developer use to persuade their manager?
Choose 3 answers:

Question57: A developer has an ErrorHandler module that contains multiple functions.
What kind of export be leverages so that multiple functions can be used?

Question58: A developer is wondering whether to use, Promise.then or Promise.catch, especially when a Promise throws an error?
Which two promises are rejected?
Which 2 are correct?

Question59: Refer to the following object:
const cat ={
firstName: 'Fancy',
lastName: ' Whiskers',
Get fullName() {
return this.firstName + ' ' + this.lastName;
}
};
How can a developer access the fullName property for cat?

Question60: Which javascript methods can be used to serialize an object into a string and deserialize a JSON string into an object, respectively?

Question61: 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:
<input type =" text" value="Hello" name ="input">
<button type ="button" >Display </button> 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?

Question62: A developer creates a generic function to log custom messages in the console. To do this, the function below is implemented.
01 function logStatus(status){
02 console./*Answer goes here*/{'Item status is: %s', status};
03 }
Which three console logging methods allow the use of string substitution in line 02?

Question63: Consider type coercion, what does the following expression evaluate to?
True + 3 + '100' + null

Question64: Refer to the following code:
<html lang="en">
<body>
<div onclick = "console.log('Outer message') ;">
<button id ="myButton">CLick me<button>
</div>
</body>
<script>
function displayMessage(ev) {
ev.stopPropagation();
console.log('Inner message.');
}
const elem = document.getElementById('myButton');
elem.addEventListener('click' , displayMessage);
</script>
</html>
What will the console show when the button is clicked?

Question65: is below:
<input type="file" onchange="previewFile()">
<img src="" height="200" alt="Image Preview..."/>
The JavaScript portion is:
01 function previewFile(){
02 const preview = document.querySelector('img');
03 const file = document.querySelector('input[type=file]').files[0];
04 //line 4 code
05 reader.addEventListener("load", () => {
06 preview.src = reader.result;
07 },false);
08 //line 8 code
09 }
In lines 04 and 08, which code allows the user to select an image from their local computer , and to display the image in the browser?

Question66: Refer to the code below:

Which value can a developer expect when referencing country,capital,cityString?

Question67: 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

Question68: Refer to the code below:
let o = {
get js() {
let city1 = String("st. Louis");
let city2 = String(" New York");
return {
firstCity: city1.toLowerCase(),
secondCity: city2.toLowerCase(),
}
}
}
What value can a developer expect when referencing o.js.secondCity?

Question69: Refer to the code:

Given the code above, which three properties are set pet1?
Choose 3 answers:

Question70: A developer writes the code below to calculate the factorial of a given number function sum(number){ return number * sum(number-1);
}
sum(3);
what is the result of executing the code.

Question71: Given the following code:
Counter = 0;
const logCounter = () => {
console.log(counter);
);
logCounter();
setTimeout(logCOunter, 1100);
setInterval(() => {
Counter++
logCounter();
}, 1000);
What is logged by the first four log statements?

Question72: Refer to the code below:

Which replacement for the conditional statement on line 02 allows a developer to correctly determine that a specific element, myElement on the page had been clicked?

Question73: Refer to the following code:

What is the output of line 11?

Question74: Refer to the code below:
Const searchTest = 'Yay! Salesforce is amazing!" ;
Let result1 = searchText.search(/sales/i);
Let result 21 = searchText.search(/sales/i);
console.log(result1);
console.log(result2);
After running this code, which result is displayed on the console?

Question75: A developer receives a comment from the Tech Lead that the code given below has error:
const monthName = 'July';
const year = 2019;
if(year === 2019) {
monthName = 'June';
}
Which line edit should be made to make this code run?

Question76: 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?

Question77: Refer to the following code:
function test (val) {
If (val === undefined) {
return 'Undefined values!' ;
}
if (val === null) {
return 'Null value! ';
}
return val;
}
Let x;
test(x);
What is returned by the function call on line 13?

Question78: Which two options are core Node.js modules?
Choose 2 answers

Question79: Given the following code:
document.body.addEventListener(' click ', (event) => {
if (/* CODE REPLACEMENT HERE */) {
console.log('button clicked!');
)
});
Which replacement for the conditional statement on line 02 allows a developer to correctly determine that a button on page is clicked?

Question80: Refer to the following code:
Let obj ={
Foo: 1,
Bar: 2
}
Let output =[],
for(let something in obj{
output.push(something);
}
console.log(output);
What is the output line 11?

Question81: Refer to the code snippet below:
Let array = [1, 2, 3, 4, 4, 5, 4, 4];
For (let i =0; i < array.length; i++){
if (array[i] === 4) {
array.splice(i, 1);
}
}
What is the value of the array after the code executes?

Question82: Refer to the following code:
function test (val) {
If (val === undefined) {
return 'Undefined values!' ;
}
if (val === null) {
return 'Null value! ';
}
return val;
}
Let x;
test(x);
What is returned by the function call on line 13?

Question83: A developer wants to use a try...catch statement to catch any error that countSheep () may throw and pass it to a handleError () function.
What is the correct implementation of the try...catch?
A)

B)

C)

D)

Question84: A test has a dependency on database. query. During the test, the dependency is replaced with an object called database with the method, Calculator query, that returns an array. The developer does not need to verify how many times the method has been called.
Which two test approaches describe the requirement?
Choose 2 answers

Question85: developer uses the code below to format a date.

After executing, what is the value of formattedDate?