The mass of a planet is $\frac{1}{10}$ that of the earth and its diameter is half that of the earth. The acceleration due to gravity on that planet is: (in $m \ s^{-2}$)

Which of the following statements are true about the acceleration due to gravity,$g$?
$A$. $g$ is greater at the poles.
$B$. The value of $g$ decreases with height.
$C$. The value of $g$ is the same all over the Earth.
$D$. The value of $g$ is maximum at the center of the Earth.

How can we conclude that the Earth is not a perfect sphere based on the acceleration due to gravity?

The acceleration due to gravity at a height $h$ above the surface of the $Earth$ is $g_h$. At a depth $d = 90 \text{ km}$ below the $Earth$'s surface, the acceleration due to gravity is also $g_h$. The value of $h$ is: (in $\text{ km}$)

Two planets $A$ and $B$ of radii $R$ and $1.5 R$ have densities $\rho$ and $\rho / 2$ respectively. The ratio of acceleration due to gravity at the surface of $B$ to $A$ is:

If $R$ is the radius of the Earth and $g$ is the acceleration due to gravity on the Earth's surface,then the mean density of the Earth is: