If the radius of earth were to shrink by two percent, its mass remaining the same, the acceleration due to gravity on the earth's surface would

The radius of earth is $R$ and acceleration due to gravity on its surface is $g$. The height at which the acceleration due to gravity becomes $\frac{g}{8}$ is:

A planet is 121 times heavier than moon and has a diameter 9 times that of moon. If the escape velocity on the planet is $v$, then the escape velocity on the moon will be: