If x=, find the value of x^-2.

The distance from the earth to the sun is 149600000000 m. Write it in standard form.

Mass of earth is (5.97 x 10²⁴) kg and mass of moon is (7.35 x 10²²) kg. What is the total mass of the two?

By what number should be multiplied so that the product may be equal to ?

Simplify: