2- A pneumatic vacuum lift system uses six suction cups, each having a lip with a 100-mm outside diameter and an 80-mm inside diameter. The vacuum system is to lift large steel sheets weighing 1500 N. The total volume inside the cup cavities and associated piping up to the vacuum pump is 0.20 m³. If a factor of safety of 2 is used, what flow rate must the vacuum pump deliver if the time required to produce the desired vacuum pressure is 2.0 min.?