9- Compute the pressure produced in the oil in a closed cylinder by a piston exerting a force of 12.0kN on the enclosed oil. The piston has a diameter of 75mm. 10- A hydraulic cylinder must be able to exert a force of 38.8kN. The piston diameter is 40mm. Compute the required pressure in the oil. 11- The hydraulic lift for an automobile service garage has a cylinder with a diameter of 8.0in. What pressure must the oil have to be able to lift 6000lb ? 12- A coining press is used to produce commemorative coins with the likenesses of all the U.S. presidents. The coining process requires a force of 18000lb. The hydraulic cylinder has a diameter of 2.50in. Compute the required oil pressure. 13- The maximum pressure that can be developed for a certain fluid power cylinder is 20.5MPa. Compute the force it can exert if its piston diameter is 50mm