1. A drillstring consists of 9,000 ft 5 in, 19.5 lbm/ft drillpipe, and1,000 ft of 8 in OD, 3in ID drill collars. What is the: (a) Volume of the drillpipe in bbl. (b) Volume of the drill collars in bbl (c) Number of pump cycles required to pump surface mud to the bit(duplex pump, 6 in liners, 2.5 in rods, 16 i strokes, pumping at 85 % volumetric efficiency). (d) Displacement of drillpipes in bbl/ ft (e) Displacement of drill collars in bbl/ft.