Consider the following statements:

A horizontal pipe reduced from 10 cm to 5 cm in diameter. If the pressure head at 10 cm section is 10 metres and velocity head is 1 metre, then the

i. Total head at any points is 11 metres.

ii. Pressure head at the 5 cm section is negative

iii. Discharge varies proportionate to the diameter

iv. Datum head at all sections is constant

Identify the correct statements