PLEASE HELP AGAIN

Solve for x. x - 7.9 = 1.19

The amount spent on food and drink by 20 customers is shown below what is the modal amount spent ?

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

Which of the functions below could have created this graph?