At what altitude will the acceleration due to gravity be 25% of that at the earth’s surface (given radius of earth is R) ?

At what altitude in metre will the acceleration due to gravity be 25% of that at the earth's surface? (R is the radius of the earth)

Assuming that the Earth is a sphere of radius R . At what altiude will the value of acceleration due to gravity be half its value at the surface of the Earth?

At what height above the earth's surface the acceleration due to gravity will be 1/9 th of its value at the earth’s surface? Radius of earth is 6400 km.

At what height above the earth's surface the acceleration due to gravity will be 1/9 th of its value at the earth’s surface? Radius of earth is 6400 km.

At what height above the earth's surface the acceleration due to gravity will be 1/9 th of its value at the earth’s surface? Radius of earth is 6400 km.