Which data type represents unique and immutable values in JavaScript introduced in ES6?

What is the data type of the value undefined in JavaScript?

A). Number

B). Boolean

C). String

D). Undefined

Which operator checks if an object is an instance of a specific object type in JavaScript?

A). instanceof

B). typeof

C). isInstanceof

D). isTypeOf

Which data type represents an intentional absence of any value in JavaScript?

A). Null

B). Undefined

C). String

D). Number

Which data type represents positive infinity in JavaScript?

A). Infinity

B). Number

C). NaN

D). Null

What is the data type of the value 42 in JavaScript?

A). String

B). Boolean

C). Number

D). Null

What is the outcome of typeof undefined in JavaScript?

A). String

B). Undefined

C). Null

D). Number

What is the outcome of typeof [1, 2, 3] in JavaScript?

A). String

B). Number

C). Array

D). Object

What will the following code snippet output: let a = 10; a += '5'; console.log(a); in JavaScript?

A). '105'

B). 105

C). 15

D). '15'

Which of the following is not a valid data type in JavaScript?

A). Array

B). Symbol

C). Map

D). Tuple

What will let x = '10'; let y = x - 5; console.log(y); output in JavaScript?

A). '5'

B). 5

C). '10'

D). 10