2.
it is hard to have a good example of constant velocity on earth because of

a. friction

b. weather

c. gravity

d. people

It is hard to have a good example of constant velocity on Earth because of friction.

Option A

Explanation:

As per Newton’s first law of motion, any object in an ideal system will tend to remain in its state of rest or motion unless an external force acts on the object. But it is the ideal case which indicates the constant velocity of any object.

But in non-ideal cases, the presence of friction will lead to falsify the first law in case of motion of an object. As any object in motion will tend to slow down irrespective of any external force due to friction thus cancelling the first law of motion. So the friction of air or water or any kind of medium will make it hard to have a good example of constant velocity on Earth.