She claims that because the mean number of words on each page of the language arts book is greater than the mean number of words on each page of the social studies books, the language arts book has more words per pages. based on the data, is this a valid inference?

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