Use the following:
pB + (1/2)*rho*vB^2 = pA + (1/2)*rho*vA^2 pB = rho*g*h
vA*AreaA = vB*AreaB
pB + (1/2)*rho*vB^2 = pC + (1/2)*rho*vC^2 + (0.15/2)*rho*vB^2
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vC*AreaC = vB*AreaB
Volume flow rate = v*Area
v is velocity, p is static pressure
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