A model rocket is launched from the roof of a building. Its flight path is modeled by h = -5t +30t +10 where h is

A model rocket is launched from the roof of a building. Its flight path is modeled by h = -5t² +30t +10 where h is the height of the rocket above the ground in metres and t is the time after the launch in seconds.What is the rocket's maximum height?When did the rocket reach its maximum height?