I need to solve it

A 10000 ft drill string consists of 6", 21.5 Ib/ft drill pipes and 2000 ft of 8"/2.5" drill collars is used to drill a well. The duplex pump has stroked 7000 strokes to make one cycle of the mud. Use below data to calculate the hole size. Rod diameter: 2.5" Liner diameter: 6.5" Stroke length: 10" Pump volumetric efficiency: 0.92 Pump mechanical efficiency: 0.88 Surface tubular capacity: 12 bbls