Miles traveled, miles to go, fill in the “?”

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

Find two consexutive odd integers such that the sum of their square is 650

In the equation sqrt(n+5)-sqrt(11-10)=1. what is the value of n