The path of a rocket flying through the air is given by the equation h(t)= -0.5t^2+3t+5, where h(t) is the height of the rocket (in feet) at any time, t (in seconds)
a. How long does it take the rocket to reach its maximum height?
b.What is the rocket's maximum height?
c.How long does it take the rocket to land?
d.When will the rocket be 42 feet off the ground?

i got a maximum height of 9.5 i just cant figure out the time and other stuff which is a. c. and d.help? thanks!