Determine the contact size in square inches (per side) for the fingers of a parallel gripper to meet the following specifications: rubber coated aluminum contact surfaces with a use (coefficient of static friction) of 0.77, part that is a cardboard box weighing 210 newtons and capable of withstanding a maximum pressure of 1.4 psi, application of a 26 percent lifting safety factor, and a maximum vertical acceleration of the robot arm of 30 centimeters per second squared. (Enter your answer as a number without the units.)