Its a very syplel thing devipe it by distance and boom u shude have it
Answer:

Explanation:
From the question we are told that:
Time 
Generally the Period is given as

Therefore difference in frequency dF



The 2nd Law of Motion states acceleration is produced when a n unbalanced force acts on an object (mass) The more mass the object has the more net force has to be used to move it.
Examples:
If you use the same force to push a truck and push a car, the car will have more acceleration than the truck, because the car has less mass.
It's easier to push a empty shopping cart then a full one, because the full one has more mass than the empty one. This means more force is required to push the full shopping cart.
The concave lens is a diverging lens, because it causes the light rays to bend away (diverge) from its axis. In this case, the lens has been shaped so that all light rays entering it parallel to its axis appear to originate from the same point, F, defined to be the focal point of a diverging lens.