Insulin is secreted by :
Which of the following diseases is not caused by virus ?
Man first landed on the surface of the Moon in :
Which one of the following is a chemical change ?
Sound travels fastest in
Aurora Borealis is a light phenomenon seen at night in the:
The weight of a person on the surface of the moon will be about one-sixth of his weight on the surface of the earth. This is because
Measles is a disease caused by :
A solar eclipse occurs when the :
Which layer of the atmosphere is nearest to the surface of the earth?