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Assume that wet concrete $(\backslash$gamma $=150$ lbf$/$ft$^3)$ behaves as a liquid. Determine the hydrostatic force per unit foot of length $($in the page$)$ exerted on the forms by the concrete if h $=12$ ft$.$ What force is exerted on the bottom tie if the forms are held in place as shown, with ties to brace the vertical forms spaced every $3$ ft $($this is the distance into the page between sets of bottom and top ties$).$

$($Please disregard the $9$ft from the diagram$)$