In the school used on a blueprint, 1/4 inch represents 3 feet. On the blueprint what is the length of the room with an actual length of 30 feet?

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

How many ordered pairs of positive integers satisfy xy=32?

Find the solution on the interval [0, 2pi)