It is necessary to deliver 5 L/min of a water-glycerol solution (sp gr. = l.l ; v = l.03 × 10-5 m2/ sec) under a pressure head of 50 mm Hg. A glass tube is used (e = 0 .003 mm). Determine the tube diameter if the tube length is 2.5 m. Assume the pressure head (50 mm Hg) is needed to overcome the friction Joss in the horizontal tube; no other losses are considered.