Javascript Dev 1 Cert

Question 1

What are 3 ways to create Objects?

Answer 1

1. Object literal
2. Object constructor
3. Object.create()

Question 2

What way is this Object being instantiated?

var x = {}
var detail = {
                name: "nikhil"
}

Answer 2

Object literal

Question 3

What way is this Object being instantiated?

var x = new Object()
x.name = "nikhil"
console.log(x)

Answer 3

Object constructor

Question 4

What way is this Object being instantiated?

var obj = {
          name: "nikhil"
			 }
var newObj = Object.create(obj)

Answer 4

Object.create() method

Question 5

What is the output?

typeof 23.783

Answer 5

Number

Question 6

What is the output?

typeof NaN

Answer 6

Number

Question 7

What is the output?

typeof 0

Answer 7

Number

Question 8

What is the output?

typeof 0

Answer 8

Number

Question 9

What is the output?

typeof "true"

Answer 9

String

Question 10

What is the output?

var x
typeof x

Answer 10

undefined

Question 11

What is the output?

typeof null

Answer 11

object

Question 12

What is the output?

typeof {}

Answer 12

object

Question 13

What is the output?

typeof !!(1)

Answer 13

Boolean

Question 14

What is the output?

typeof function () { }

Answer 14

function

Question 15

What is the output?

typeof new Date()

Answer 15

Object

Question 16

What is the output?

String(23)

Answer 16

‘23’

Question 17

What is the output?

String(undefined)

Answer 17

‘undefined’

Question 18

What is the output?

String(null)

Answer 18

‘null’

Question 19

What is the output?

String("23")

Answer 19

‘23’

Question 20

What is the output?

String(true)

Answer 20

‘true’

Question 21

What is the output?

Number(null)

Answer 21

0

Question 22

What is the output?

Number(undefined)

Answer 22

NaN

Question 23

What is the output?

Number('hello')

Answer 23

NaN

Question 24

What is the output?

Number([])

Answer 24

0

Question 25

What is the output?

Number([33, 33])

Answer 25

NaN

Question 26

What is the output?

Number(['523'])

Answer 26

523

Question 27

What is the output?

Number([63.45])

Answer 27

63.45

Question 28

What is the output?

Boolean('')

Answer 28

false

Question 29

What is the output?

Boolean(' ')

Answer 29

true

Question 30

What is the output?

Boolean(undefined)

Answer 30

false

Question 31

What is the output?

Boolean(null)

Answer 31

false

Question 32

What is the output?

Boolean(NaN)

Answer 32

false

Question 33

What is the output?

100 == "100"

Answer 33

true

Question 34

What is the output?

100 === "100"

Answer 34

false

Question 35

What is the output?

true == 1

Answer 35

true

Question 36

What is the output?

true === 1

Answer 36

false

Question 37

What is the output?

NaN === NaN

Answer 37

false

Question 38

What is the output?

- 0 == 0

Answer 38

true

Question 39

What is the output?

NaN == NaN

Answer 39

false

Question 40

What is the output?

- 0 === 0

Answer 40

true

Question 41

What is the output?

[] === []

Answer 41

false

Question 42

What is the output?

[] == []

Answer 42

false

Question 43

What is the output?

Object.is(100, "100")

Answer 43

false

Question 44

What is the output?

var x = 10
console.log(x++)

Answer 44

10

Question 45

What is the output?

var x = 10
x++
console.log(x);

Answer 45

11

Question 46

What is the output?

var x = []
var y = x
x === y

Answer 46

true

Question 47

What is the output?

"Hello" + "World"
    \+ "16546542"

Answer 47

‘HelloWorld16546542’

Question 48

What is the output?

100 + "world"

Answer 48

‘100world’

Question 49

What is the output?

100 + null + 20 + "world"

Answer 49

‘120world’

Question 50

What is the output?

true + 1 + "hey"

Answer 50

‘2hey’

Question 51

What is the output?

undefined + 2

Answer 51

NaN

Question 52

What is the output?

100 + 200 + undefined + "hey"

Answer 52

NaNhey

Question 53

What is the output?

undefined + 2

Answer 53

NaN