The number of bones in an adult human body is:

Which of the following is an example of a chemical change?

Which of the following is used in vaccines to build immunity?

The device used to convert mechanical energy into electrical energy is:

The primary source of energy for most ecosystems is:

The main gas responsible for global warming is:

Which of the following gases is used in fire extinguishers?

Which scientist discovered the law of gravitation?

The process by which solid turns directly into gas without becoming liquid is called:

The condition in which blood sugar levels are abnormally high is called:

Which of the following is the powerhouse of the cell?