Answer:

Step-by-step explanation:
The rate of volume flow out of tank can be expressed as:

where,
dV/dt = Volume flow rate
A = Cross-sectional area of outlet = πd²/4
d = diameter of circular outlet
dL = Displacement covered by water
dt = time taken
but we know that:
Velocity = υ = displacement/time = dL/dt
Substituting the values of "dL/dt" and "A" in the equation, we get:

This is the expression for volume flow rate dV/dt, on terms pf v, d.