please show work thank you 18 ft d2 d1 36 Figure 2 SolutionT

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18 ft d2 d1 36° Figure 2:

The pressure distribution at the left wall will be linearly varying because of the pressure being hydrostatic in nature

The centroid of the pressure diagram will be at 18/3=6 ft from the bottom of the tank

Therefore,correct answer is option (d) 6 ft