An airplane is change in alitude before landing is shown in the table

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

An airplane travels at an unknown elevation before it descends 3 miles to an elevation of 15 miles. find the elevation of the plane before its descen.

On #16 : explain how factoring a trinomial, ax^2+ bx+ c, when a does not equal 1 different from factoring a trinomial when a = 1.