Question 1

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 tocorrectly determine that a button on page is clicked?

Options :

A : Event.clicked

B : e.nodeTarget ==this

C : event.target.nodeName == 'BUTTON'

D : button.addEventListener('click')

Answer: C

Question 2

A developer is setting up a new Node.js server with a client library that is built using events and callbacks.The library:Will establish a web socket connection and handle receipt of messages to the serverWill be imported with require, and made available with a variable called we.The developer also wants to add error logging if a connection fails.Given this info, which code segment shows the correct way to set up a client with two events that listen at execution time?

Options :

A : ws.connect (( ) => {console.log('connected to client'); }).catch((error) => { console.log('ERROR' , error); }};

B : ws.on ('connect', ( ) => {console.log('connected to client'); ws.on('error', (error) => { console.log('ERROR' , error); });});

C : ws.on ('connect', ( ) => { console.log('connected to client'); }}; ws.on('error', (error) => { console.log('ERROR' , error); }};

D : try{ws.connect (( ) => {console.log('connected to client'); });} catch(error) { console.log('ERROR' , error); };}

Answer: C

Question 3

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''. Capture What can the developer do to change the code to print ''Hello World'' ?

Options :

A : Change line 7 to ) () ;

B : Change line 2 to console.log('Hello' , name() );

C : Change line 9 to sayHello(world) ();

D : Change line 5 to function world ( ) {

Answer: B

Question 4

Refer to the following code:class Vehicle{constructor(plate){this.plate = plate;}}class Truck extends Vehicle{constructor(plate, weight){//Missing codethis.weight = weight;}displayWeight(){console.log(`The truck ${this.plate} has a weight of ${this.weight}lb.`);}}let myTruck = new Truck('123Ab',5000);myTruck.displayWeight();Which statement should be added to missing code for the code to display 'The truck 123AB has aweight of 5000lb.

Options :

A : super(plate)

B : super.plate = plate

C : Vehicle.plate = plate

D : this.plate = plate

Answer: A

Question 5

What is the result of the code block?

Options :

A : The console logs only 'flag'.

B : The console logs 'flag' and another flag.

C : An error is thrown.

D : The console logs 'flag' and then an error is thrown.

Answer: D

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