20 The vertices of a rectangle are A (2,-2), B (4, -6), C (4,-2), and D (2,-2). If the rectangle is dilated by a scale factor of 1/2 what will be the coordinates of B'?

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