Identify the correct statement regarding open channel hydraulics.

If the goal is to design the most economical open channel flow section which minimizes head loss and bed deposition, what is the ideal cross-sectional shape?

Which of the following is defined as the vertical distance of the lowest point of a channel section from the free surface of water?

For the most economical trapezoidal channel section, the length of one of the sloping sides must be equal to:

Choose the correct statement(s) from the following options related to flow through an open channel: i. The flow in which depth of flow changes abruptly over a small length of the channel is known as Gradually Varied Flow. ii. If at any point in open channel flow, the velocity, depth, or rate of flow changes with respect to time, then the flow is said to be steady flow. iii. If for a given length of the channel, the velocity of flow, depth of flow, slope of the channel, and cross-section do not remain constant, the flow is known as non-uniform flow.

In a hydraulically most efficient trapezoidal channel section, the ratio of the bed width to the depth is: