State whether the following statement is True or False:
The acceleration due to gravity $g$ is given by the formula $g = GM/R^2$,where symbols have their usual meanings.

State the source of centripetal force that our earth requires to revolve around the sun. List the factors on which this force depends.

State whether the following statement is True or False:
The inertia of an object depends upon its mass.

$A$ stone is dropped from the edge of a roof. It passes a window $2 \, m$ high in $0.1 \, s$. How far is the roof above the top of the window?

The value of $g$ on the earth's surface is $9.8 \, m s^{-2}$. Suppose the earth suddenly shrinks to one-third of its present size without losing any mass. What is the value of $g$ on the surface of the shrunk earth (in $, m s^{-2}$)?

State whether the following statement is True or False:
All objects attract each other along the line joining their centre of mass.