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

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

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 will be the result of the following code: let z = '123'; z = Number(z); console.log(typeof z);?

A). string

B). number

C). undefined

D). boolean

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

A). number

B). boolean

C). string

D). object

What does the isNaN function do?

A). Checks if a value is not a number

B). Converts a value to a number

C). Checks if a value is a number

D). Converts a value to NaN

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

A). number

B). string

C). NaN

D). undefined

What does it mean that JavaScript is dynamically typed?

A). Variables do not have types

B). Variables can change type

C). Variables must be declared with a type

D). Variables cannot change type

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

A). null

B). string

C). object

D). undefined

Which type conversion happens automatically in the expression 3 + '5'?

A). Number to String

B). String to Number

C). Boolean to String

D). Number to Boolean

Which of the following values is considered falsy in JavaScript?

A). 1

B). 0

C). 0

D). {}