A hemispherical tank of radius (R) has an orifice of cross-sectional area (a) at its bottom and is full of liquid. The time required to empty the tank completely is

A. 14π R1/2/15Cd × a √(2g)

B. 14π R3/2/15Cd × a √(2g)

C. 14π R5/2/15Cd × a √(2g)

D. 14π R7/2/15Cd × a √(2g)

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