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

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

A). null

B). string

C). object

D). undefined

What is the result of the following code: let x = 5; x = 'hello'; console.log(typeof x);?

A). number

B). string

C). undefined

D). object

What will be the result of typeof function() {} in JavaScript?

A). function

B). object

C). undefined

D). method

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

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 result of typeof [] in JavaScript?

A). array

B). object

C). list

D). undefined

What will typeof null return in JavaScript?

A). null

B). undefined

C). object

D). number

What will typeof NaN return in JavaScript?

A). number

B). NaN

C). undefined

D). object

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

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

A). number

B). boolean

C). string

D). object