QUESTION: 13

A developer is creating a simple webpage with a button.
When a userclicks this button for the first time, a message is displayed.
The developer wrote the JavaScript code below, but something is missing. The message gets displayed every time a user clicks the button, instead of just the first time.
01 functionlisten(event) {
02 alert ( `Hey! I am John Doe') ;
03 button.addEventListener (`click', listen);
Which two code lines make this code work as required?
Choose 2 answers

On line 02, use event.first to test if it is the first execution.
On line 04, useevent.stopPropagation ( ),
On line 04, use button.removeEventListener(` click" , listen);
On line 06, add an option called once to button.addEventListener().

Answer(s): C,D

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QUESTION: 14

A developer uses a parsed JSON string to work with user information as in the block below:
01 const userInformation ={

02 " id " : "user-01",
03 "email" : "user01@universalcontainers.demo",
04 "age" : 25
Which two options access the email attribute in the object? Choose 2 answers

userInformation("email")
userInformation.get("email")
userInformation.email
userInformation(email)

Answer(s): A,C

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QUESTION: 15

Refer to the code below:
01 const server = require(`server');
02 /* Insert code here */
A developer imports a library that creates a web server. Theimported 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 ?

Server.start ();
server.on(` connect ' , ( port) => {console.log(`Listening on ' , port) ;})
server()
serve(( port) => (
console.log( `Listening on ', port) ;

Answer(s): B

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QUESTION: 16

A developer wants to iterate through an array of objects and count the objects and count the objects whose property value, name, starts with the letterN. Const arrObj = [{"name" : "Zach"} , {"name" : "Kate"},{"name" : "Alise"},{"name" : "Bob"},{"name" :
"Natham"},{"name" : "nathaniel"}
Refer to the code snippet below:
01 arrObj.reduce(( acc, curr) => {
02 //missing line 02
02 //missing line 03
04 ). 0);
Which missing lines 02 and 03 return the correct count?

Const sum = curr.startsWith(`N') ? 1: 0;Return acc +sum
Const sum = curr.name.startsWith(`N') ? 1: 0;Return acc +sum
Const sum = curr.startsWIth(`N') ? 1: 0;Return curr+ sum
Const sum =curr.name.startsWIth(`N') ? 1: 0;Return curr+ sum

Answer(s): B

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QUESTION: 16

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