If the distance between two objects is doubled,the gravitational force between them :

Earth is continuously pulling the moon towards its centre,still it does not fall to the earth,why?

Why does a body weigh more at the poles than at the equator?

An object is placed one by one in three liquids having different densities. The object floats with $\frac{1}{9}$, $\frac{2}{11}$, and $\frac{3}{7}$ parts of its volume outside the liquid surface in liquids of densities $d_1$, $d_2$, and $d_3$ respectively. Which of the following statements is correct?

Give reason: $A$ stone falls towards the earth,but the earth does not rise towards the stone.

$A$ stone is dropped from a height of $20\, m$.
$(a)$ How long will it take to reach the ground?
$(b)$ What will be its speed when it hits the ground? $(g=10\, m s^{-2})$