Plz 30 points answer only if you know
the correct formula for finding the relative velocity of an object is:
v a/c = v a/b - v b/c
v a/c = v a/b + v b/c
v a/b = v a/b + v b/c
v b/c = v a/b + v b/c

v a/c = v a/b + v b/c

Explanation:

Assuming you are saying Velocity of A relative to C as v a/c (I'm sorry I have not seen this format in over local texts )

Using the triangle of velocity you can arrive at this equation,

Velocity of A relative to C = Velocity of A relative to B + Velocity of B relative to C.

Consider a car travelling on Earth with a passenger while you walk on the road. So your velocity as seen by passenger is,

Velocity of you relative to passenger = Velocity of you relative to Earth + Velocity of Earth relative to passenger.

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.