Answer
$$F = 1497.6{\text{lb}}$$
Work Step by Step
$$\eqalign{
& {\text{The weight}} - {\text{density of water is 62}}.{\text{4 pounds per cubic}} \cr
& {\text{foot, and the sheet is submerged in 8 feet of water}}{\text{.}} \cr
& {\text{The fluid pressure is:}} \cr
& P = wh \cr
& P = \left( {62.4} \right)\left( 8 \right) \cr
& P = 499.2 \cr
& {\text{The fluid force is}} \cr
& F = PA \cr
& F = \left( {499.2} \right)\left( 3 \right) \cr
& F = 1497.6{\text{lb}} \cr} $$
