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The pressure drop through a well-designed constriction is to be used for measuring the velocity of flow through a circular pipe. If the pressure drop from a 0.1m diameter section to a 0.05m diameter section of the pipe is 7.5kPa, the velocity in ms1 in the 0.1m diameter section of the pipe is (Take density of liquid =1000kgm3 ) (A) 0.5 (B) 1.0 (C) 1.5 (D) 2.0