A pitot-static tube measures the total pressure pT and the local pressure p in a uniform ?ow in a 4-cm- diameter water pipe. Calculate the ?ow rate if:
(a) pT ¼ 1500 mm of mercury and p ¼ 150 kPa
(b) pT ¼ 250 kPa and p ¼ 800 mm of mercury
(c) pT ¼ 900 mm of mercury and p ¼ 110 kPa
(d) pT ¼ 10 in. of water and p ¼ 30 lb=ft2