A liquid flows through a horizontal tube. The velocities of the liquid in the two sections, which have areas of cross section `A_(1)` and `A_(2)` are `v_(1)` and `v_(2)` respectively. The difference in the levels of the liquid in the two vertical tubes is `h`. Then
A. The volume of the liquid flowing through the tube in unit time is `A_1v_1`
B. `v_2-v_1=sqrt(2gh)`
C. `v_2^2-v_1^2=2gh`
D. The energy per unit mass of the liquid is the same in both sections of the tube
