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 data type of the value 42 in JavaScript?
A). String
B). Boolean
C). Number
D). Null
Which of the following is a primitive data type in JavaScript?
A). Object
B). Array
C). Function
D). Boolean
Which data type represents unique and immutable values in JavaScript introduced in ES6?
A). Symbol
B). Object
C). Array
D). Function
What is the outcome of typeof [1, 2, 3] in JavaScript?
A). String
B). Number
C). Array
D). Object
What is the data type of the value undefined in JavaScript?
A). Number
B). Boolean
C). String
D). Undefined
What does NaN represent in JavaScript?
A). Not a Number
B). Infinity
C). Positive Infinity
D). Negative Infinity
Which data type represents an intentional absence of any value in JavaScript?
A). Null
B). Undefined
C). String
D). Number
What will be the result of typeof 'hello' in JavaScript?
A). String
B). Number
C). Undefined
D). Function
What is the data type of the value 'null' (with quotes) in JavaScript?
A). String
B). Number
C). Null
D). Undefined