Is the graphed function linear?

What is 1/2 x (6 x 4)+3 + 2 show your work

Jonah runs 3/5 miles on sunday and 7/10 mile on monday. he uses the model to find that he can ran a total of 1 mile . what mistake does jonah make

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