A lake discharges into a steep channel. At the channel entrance the lake level is 2.5 m above the channel bottom. Neglecting losses, find the discharge for the following geometries:
(a) Rectangular section, b = 4 m
(b) Trapezoidal section, b = 3 m, m1 = m2 = 2.5
(c) Circular section, d = 3.5 m