Differentiate between mass and weight.

Give Reasons for the Following:

As we go higher above the surface of the earth the weight of the body decreases

Give Reasons for the Following:

If the force of gravity acts on all bodies proportional to their masses, why does a heavy body not faster than a light body?

Under what conditions a body becomes weightless?

If we go deeper inside the earth, what will change: weight or mass or both, why?