Can someone explain me the logic behind this question

Question

A raindrop has a mass of 7.5  10^-7 kg and is falling near the surface of the earth. Calculate the magnitude of the gravitational force exerted in the following.

a) on the raindrop by the earth

b)on the earth by the raindrop

Thank you!

Answer 1

The Earth and the raindrop are two objects with a certain mass, let say m1 for the Earth and m2 for the raindrop. Therefore, there is a force between these two objects. This force depends on the distance between the objects which in the problem is not stated. However, by Newton's third law (action-reaction) the magnitude of the force exerted by the raindrop by the Earth is the same as the force exerted by the Earth on the raindrop.

Best,

Davide