Mass divided by volume is equal to?

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?

Will give let f(x)=2x and g(x)=[tex]2^{x}[/tex] graph the functions on the same coordinate plane. what are the solutions to the equation f(x)=g(x) ? enter your answers in the boxes x=[? ] or x=[? ]

Arock was dropped from the top of a building. the function that describes the height after it was dropped is f(x)=64-16x^2. what are the zeros of the function and what do they mean?