Given the code: let y = 10; y = true;, what is the type of y after execution?

What is the type of the value returned by parseFloat('3.14abc')?

A). number

B). string

C). NaN

D). undefined

What is the result of typeof [] in JavaScript?

A). array

B). object

C). list

D). undefined

What is the type of the value returned by JSON.parse('null')?

A). null

B). string

C). object

D). undefined

Which of the following values is considered falsy in JavaScript?

A). 1

B). 0

C). 0

D). {}

What does the parseInt function do in JavaScript?

A). Converts a number to a string

B). Converts a string to an integer

C). Converts a boolean to a number

D). Converts an array to a number

What is the initial type of a variable declared with let a;?

A). null

B). number

C). undefined

D). object

Given let a = '10'; let b = 20;, what is the result of a + b?

A). 30

B). 1020

C). 30

D). NaN

How can you check if a variable is an array in JavaScript?

A). typeof variable === 'array'

B). Array.isArray(variable)

C). variable instanceof array

D). variable.constructor === array

What happens when you add a number and a string in JavaScript?

A). An error is thrown

B). The number is converted to a string

C). The string is converted to a number

D). Both are converted to boolean

Which operator is used to determine the type of a variable in JavaScript?

A). typeof

B). instanceof

C). type

D). isType