Answer:
when he uses more force to hit the drum then its makes a louder sound so the more force you hit the drum with then the louder it is.
Answer:

Explanation:
We have:
diameter of the wheel, 
weight of the wheel, 
mass of hanging object to the wheel, 
speed of the hanging mass after the descend, 
height of descend, 
(a)
moment of inertia of wheel about its central axis:




Concaved lenses...........
Answer: in the smaller/ thinner pieces.
Answer:27 km per hour West + 17 km per hour North