The function h(t)=−16t2+75t+80 models the height of a ball as it is thrown into the air, where h is in feet and t is in seconds. What is the height of the ball once 5 seconds have passed?

Apinhole camera is made out of a light-tight box with a piece of film attached to one side and pinhole on the opposite side. the optimum diameter d(in millimeters) of the pinhole can be modeled by d=1.9[ (5.5 x 10^-4) l) ] ^1/2, where l is the length of the camera box (in millimeters). what is the optimum diameter for a pinhole camera if the camera box has a length of 10 centimeters