The layer of rocks which forms the surface of earth is called -----------

Which is the richest gas present in Earth?

Polestar appears vertically overhead at the ----------- .

Which is the only natural satellite of earth?

The presence of which factor made life possible on earth?

Which is the hottest planet in the solar system?

Which position does the Earth stands in terms of size in our solar system?

From the following which indicates the percentage of water present on earth surface?

What is the average speed of the revolution of the Moon around Earth?

From the following which is the optimum distance between sun and earth.