The general formula is,

Thus,

And,

The decelleration is,

feet per second per second.

Thus,

Make height is when velocity is null.b) How long would it take for the boulder to reach its maximum height?

The velocity equation is the derivative of this,

Make it zero and solve,

seconds.

After 5 seconds it reaches maximum height.c) Would it be possible for a boulder fired from this catapult to pass over a hill 300 ft high, and hit the castle on the other side? Explain to me this one because it's confusing me =[

Which is,

. Evaluate the height at five and see whether it exceedes 300 or not.