The velocity distribution in certain river cross section show that the velocity equation at vertical section is given by:

U= ((y0^2)/4a) * (1.4536+(1.76 y/y0) -(y/y0 )^2 )
In which: a = 0.0047 (Y*S)^((-2/3))
(Y):is measured from the river bed,and
(Y0 ):is the total depth of the river.
It is required to drive an expression for:
Surface velocity
Bottom velocity