The function h(x) is defined as shown. What is the range of h(x)

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

Having a hard time understanding this question (see attachment).

If my mom gets $13.05 an hour, and she works from 3: 30 to 10: 45 in the morning, how much money does my mom make?