Mario starts with a piece of construction paper that is 10 inches by 12 inches. He then cuts out a square piece from each corner of the construction paper. If each of the square pieces are 3 inches on an edge, which expression
represents the area of the paper left over?

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