Answer:
I think its 12
Step-by-step explanation:
1.
Height h = 240 feet
We insert it into formula.

Now we solve this for t:

We have two answers as the rocket will pass this height on it's way up and down.
2.
Height h = 0 feet
We insert it into formula.

Now we solve this for t:

We do not consider solution -1 as the time can not be negative. Our solution is 5s.
3.
Height at bottom of hill h = 0 feet
We insert it into formula.
Answer:
use a graph
Step-by-step explanation: