Aball is thrown into the air. the height h, in feet, of the ball can be modeled by the equation h= -16t^2 + 20t + 6, where t is the time, in seconds, the ball is in the air. when will the ball hit the ground?

Rob spent 25%, percent more time on his research project than he had planned. he spent an extra h hours on the project. which of the following expressions could represent the number of hours rob actually spent on the project? two answers