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

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

A). '5'

B). 5

C). '10'

D). 10

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

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

A). Array

B). Symbol

C). Map

D). Tuple

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'

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

A). String

B). Number

C). Array

D). Object

Which of the following is a primitive data type in JavaScript?

A). Object

B). Array

C). Function

D). Boolean

What will let x = null; console.log(typeof x); output in JavaScript?

A). Object

B). Null

C). Undefined

D). Number

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

A). instanceof

B). typeof

C). isInstanceof

D). isTypeOf

What will be the result of typeof 'hello' in JavaScript?

A). String

B). Number

C). Undefined

D). Function