Our algebra I class is working on factoring using the distributive property. And there is a word problem on homework that I simply don't even no where to start. Here it is:

Miss Moore's science class launched a rocket at ground level with in an initial upward velocity of 60 feet per second. The heighthof the rocket in feet above the ground aftertseconds is modeled by the equation h=60t-16t^2. How long was the rocket in the air before it returned to the ground?