$5.($a$)$ Water flows over a rectangular weir at $15$ cm head over its crest. If the length of weir is $1$ m and $C_d=0\mathrm{.}62$ find the discharge. Afterwards if

$3+2$

$=5$

this water flows over a right$-$angled triangular weir of $C_d=0\mathrm{.}6$ find the head over the crest of triangular weir.