The mean on a statewide geography test was 74 with a standard deviation of 12. West County sampled the scores of some of its students and reported a mean of 79 with a margin
of error of +1.9.
To the nearest whole number, how many students were in West County's sample?

How do i do this activity, is appreciated

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

The tree filled 3/4 of a cup in 1/2 and hour at what rate does syurup flow from the tree