PLEASE EXPLAIN THE STEPS :A tank containing oil has a pressure at point O of $\backslash (525\backslash$mathrm$\{$lb$\}/\backslash$mathrm$\{$ft$\}^\{2\}\backslash )$ as shown. The tank has a width $($into the paper$)$ of $10$ ft $.$ The oil is kept from draining out of the tank by the circular section A$-$B$,$ hinged at point B $,$ with a spring force $\backslash (\backslash$left$(\backslash$mathrm$\{$F$\}\_\{\backslash$mathrm$\{$s$\}\}\backslash$right$)\backslash )$ acting as shown. The density of water is $\backslash (62\mathrm{.}4\backslash$mathrm$\{$lb$\}/\backslash$mathrm$\{$ft$\}^\{3\}\backslash ).$ The specific gravity of the oil is $0\mathrm{.}802.$

Find:

$1.$ The pressure at point K $.(3$ points$)$

$2.$ The force on the top surface of the tank $($K$-$L$-$M$-$N$).(3$ points$)$

$3.$ The force on surface A$-$B resulting from the oil pressure $\backslash (\backslash$left$($F$\_\{$p$\}\backslash$right$)\backslash ).(3$ points$)$

$4.$ The minimum spring force necessary to hold the gate $\backslash (\backslash$mathrm$\{$A$\}-\backslash$mathrm$\{$B$\}\backslash )$ shut. $(1$ point$)$