What does it mean that JavaScript is dynamically typed?

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

A). null

B). number

C). undefined

D). object

What will typeof null return in JavaScript?

A). null

B). undefined

C). object

D). number

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 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

In JavaScript, what will be the type of a variable x after x = 5 + true;?

A). number

B). string

C). boolean

D). undefined

What will typeof NaN return in JavaScript?

A). number

B). NaN

C). undefined

D). object

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

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

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

A). 30

B). 1020

C). 30

D). NaN

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