a) (10 marks) Lubricating oil (Newtonian; v=1.5105m2/s ) flows steadily at 14.7L/min through a tube that is 18mm in diameter. If the tube is 152m long and rises a vertical height of 12m over its length, find: i. The entrance length required to ensure fully developed flow ii. The pressure drop iii. The frictional pressure gradient iv. The frictional energy loss v. The head loss, hL It may be useful to know that under shut-down conditions (Q=0), the measured pressure drop is 93.0kPa. b) (10 marks) Water at 20C flows down a vertical pipe under conditions where the measured pressure drop is zero. Find the range of pipe diameters D (if any) for which the flow is definitely laminar