Integers are irrational numbers. sometimes never always

Write a function for a rotation 90 degrees counter clockwise about the origin, point 0

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

Astraight water slide is 175 feet above ground and is 200 feet long. what is the angle of depression to the bottom of the slide?