Answer:
a. 
b. 
Explanation:
Using the triangle theorem both triangle the woman makes between the light so the rate of change of length can use geometry first

Solve to find the rate relation


Now the rate of the change rate


Finally the rate of her shadow moving


Wouldn't everything fall?
Explanation:
That`s is the answer, just check
Hard surfaces reflect sound back into the room, while carpets help to absorb the sound so it reflects less