A political action committee wanted to estimate the proportion of county residents who support the installation of red-light cameras throughout the county. They took a random sample of 800 county residents and found that the proportion who wanted to install these cameras was 25% with a margin of error of +/- 4% (with 95% confidence). This implies:

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