Which gas is essential for respiration in humans?

The unit of electric current is:

Which organ pumps blood in the human body?

Which planet is known as the Red Planet?

What does CPU stand for?

What does WWW stand for?

Which of the following is an operating system?

Which simple machine is a seesaw?

Which material is commonly used for electrical wiring?

Which engineering field deals with machines and engines?

What is the square of 4?

Which number comes next in the series: 2, 4, 6, __ ?

How many sides does a triangle have?

Which planet is closest to the Sun?

How many degrees are there in a right angle?