The flow net is shown in the figure below. Taking the coefficient of permeability as $4\mathrm{.}8{10}^{-6}c\frac{m}{s},$ determine:

a$)$ How high the water will rise if piezometers are placed at point a$,$ b$,$ c$,$ and d$,$ if $H_1=15m,$ and $H_2=3m$

b$)$ The total rate of seepage per unit length if $H_1=20m,$ and $H_2=7m$