A contracted $($two$-$end contraction$)$ rectangular weir with length,

L of $3\mathrm{.}0$ meters and height, P of $1\mathrm{.}5$ meters is to be installed in

a small river. The current average depth of the river is $0\mathrm{.}5$

meter with velocity of $0\mathrm{.}35$ m$/$s and width of $5\mathrm{.}0$ meters.

Determine the $($a$)$ head above the weir and the $($b$)$ depth of the

river after the contracted rectangular weir has been installed.

Use Francis Formula for the rectangular weir.