Q$4)$

A weir has a solid horizontal floor length of $40m$ with two lines of cutoff $5m$ depth below the river bed at its two ends. The floor thickness is $5m$ at the upstream end and $2m$ at downstream end, with its upper level being in flush with the river bed. For an effective head of $4m$ over the weir, calculate the uplift pressure at the two inside comer points $($junction of bottom of floor with the cutoff$)$ and also exit gradient.