Hazel is going on vacation and taking her dog Pickles along. Pickles eats 3 cups of Hungry Hound dog food each day. Hazel wants to know how many days she can feed Pickles from a 15-cup bag of Hungry Hound. Write an equation to represent this problem, then solve for d.

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