JavaScript Fundamentals Quiz

Which keyword is used to declare a variable in JavaScript?

• a.var

• b.let

• c.const

• d.All of the above

What will typeof true return?

• undefined
• number
• string
• boolean

How do you write a comment in JavaScript?

• a.<-- This is a comment -->

• b.#This is a comment

• c.//This is a comment

• d.'This is a comment'

How do you declare an array in JavaScript?

• a.let arr={};

• b.let arr=[];

• c.let arr=();

• d.let arr=<>;

Which of the following is NOT a JavaScript data type?

• a.undefined

• b.string

• c.integer

• d.number

What is the index of the first element in an array in JavaScript?

• a.0

• b.1

• c.-1

• d.Depends on the array

How do you declare a constant variable in JavaScript?

• a.var

• b.const

• c.let

• d.static

What is the correct syntax to output something to the console in JavaScript?

• a.console.print()

• b.print()

• c.console.log()

• d.log()

What is the value of x in the following code: let x=1000 % 42;?

• 50
• 34
• 24
• 42

Which of the following is a falsy value in JavaScript?

• a.'10'

• b.1

• c.null

• d."false"