A toy rocket is launched straight up from the top of a building 64 ft tall at an initial velocity of 243 ft per sec. Using the function V(x)=-16t^2+vt+h, answer the following.
1. Give the function that describes the height of the rocket in terms of t?
2. Determine the time at which the rocket reaches its maximum height, and its maximum height in feet?
3. For what time interval will the rocket be more than 400 ft above the ground level?
4. for how many seconds will it hit the ground?