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 surface of the earth will the acceleration due to gravity be 25% of its value on the surface of the earth ? Assume that the radius of the earth is 6400 km .

At what height above the surface of the earth will the acceleration due to gravity be 25% of its value on the surface of the earth ? Assume that the radius of the earth is 6400 km .

The height vertically above the earth's surface at which the acceleration due to gravity becomes 1% of its value at the surface is (R is the radius of the earth)