Answer:
Also 3s.
Explanation:
Each component is independent in two dimensional motion. This means that <em>how much time does something take to reach the ground when dropped is independent from any horizontal velocity</em>. If at one run a drop lasts 3s, at another run with twice the (horizontal) velocity and same height will also last 3s, no matter what.
Answer:
Part a)

Part b)

Explanation:
Part a)
Level of sound = 75 dB
now we know that

here we know that

now we have


Part b)
Intensity of sound wave is given as

here we know that

so we have


now we know



now we have


28 degrees celsius converts to 82.4 degrees in Fahrenheit :)