Suppose that ten people, including you and a friend wearing matching outfits, line up for a group picture. How many ways can the photographer rearrange the line if she wants to keep exactly three people between you and your friend?

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

What is the correct decimal form of 12%

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?