$($i$)$ Determine the flow rate $($q$)$ beneath the structure, assuming the coefficient of

permeability $(k)=0\mathrm{.}05\frac{cm}{sec},$ using the formula:

$q=\frac{N_f}{N_d}kh$

where:

$N_f=$ number of flow channels

$N_d=$ number of potential drops

$h=$ head loss

$($ii$)$ Calculate and sketch the pressure heads beneath the structure at three points

$($for example the front, middle and rear$)$