Gravitation question bank (Physics)

A body of mass $m$ is taken from the surface of earth to a height equal to twice the radius of earth ($R_e$). The increase in potential energy will be _______.
($g$ is acceleration due to gravity at the surface of earth)

When one moves from a point $16$ km below the earth's surface to a point $16$ km above the earth's surface. The change in $g$ is approximately $\alpha$ %. The value of $\alpha$ is _____.
(Take radius of the earth $= 6400$ km.)