Aplane is traveling at 200m/s in a vehicle circle with a radius "r". at the top of the circle the passengers experience weightlessness. what is the value for "r"?

How do you solving the solution of each system using elimination?

At 6 1/2 cents per pound of string beans how much does 7 pounds cost

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