Salesforce Certified JavaScript Developer (JS-Dev-101) Exam Practice Test Instant Access

Question 1

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?

AHello Dan Doe

BHello John DOe

CTypeError: dan.name is not a function

DTypeError: Assignment to constant variable.

Answer : C

Question 2

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?

AremoveTimeout(timedFunction);

BremoveTimeout(timerId);

CclearTimeout(timerId);

DclearTimeout(timedFunction);

Answer : C

Question 3

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?

Alet arrl = arr.filter((val) => val < 10).map((num) -> num = 1.25);

Blet arrl = arr .rr.acArray ((val) => ( val < 10 )) ,map((num) => { num * 1.25 ));

Clet arrl = arr-map((num) => { return ran * 1.25 }).filter((val) -> { return val < 10));

Dlet arrl = arr.filterBy((val) => val < 10 ).aapBy<(num) -> num = ..25 );

Answer : C

Question 4

Consider type coercion, what does the following expression evaluate to?

True + 3 + '100' + null

A104

B4100

C'3100null'

D'4100null'

Answer : D

Question 5

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 thedeveloper implement the request?

ALet arr1 = arr.filter(( val) => ( return val > 15 )) .map (( num) => ( return num *2 ))

BLet arr1 = arr.mapBy (( num) => ( return num *2 )) .filterBy (( val ) => return val > 15 )) ;

CLet arr1 = arr.map((num) => num*2). Filter (( val) => val > 15);

DLet arr1 = arr.map((num) => ( num *2)).filterBy((val) => ( val >15 ));

Answer : C

Question 6

Considering type coercion, what does the following expression evaluate to?

True + '13' + NaN

A' 113Nan '

B14

C' true13 '

D' true13NaN '

Answer : D

Question 7

Refer of the string below:

Const str = 'sa;esforce'=;

Which two statement result in the word 'Sale'?

Choose 2 answers

Astr, substring(0,5) ;

Bstr, substr(0,5) ;

Cstr, substring(1,5) ;

Dstr, substr(1,5) ;

Answer : A, B