Answer:
parasites are creatures the gain benefit off of other animals usually harming them eg:ticks on dogs
Answer:60 gm
Explanation:
Given
initial velocity of ball 
Force exerted by racquet 
time period of force 
final velocity of ball 
Racquet imparts an impulse to the ball which is given by



Explanation:
It is given that,
A helicopter blade spins at exactly 100 revolutions per minute.
Its tip is 5.00 m from the center of rotation, r = 5 m
(a) Let v is the average speed of the blade tip in the helicopter’s frame of reference. Distance covered by the helicopter, 
In 100 revolutions, 
So, average speed of the blade tip in one second is given by :


v = 52.35 m/s
(b) The average velocity over one revolution is zero because the net displacement in one rotation is 0.
Hence, this is the required solution.