Simplify the expression. write the answer using scientific notation. astronomers measure large distances in light-years. one light-year is the distance that light can travel in one year, or approximately 5,880,000,000,000 miles. suppose a star is 13.4 light-years from earth. in scientific notation, how many miles away is it?

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