Answer
$F=503MN$
Work Step by Step
We know that
$P=P_{\circ}+\rho gh$
We plug in the known values to obtain:
$P=101325+10^3\times 9.8\times 11\times 10^3=108MPa$
We also know that
$R_{\circ}=\frac{D_{\circ}}{2}=\frac{121.8}{2}=60.9cm$
As $P=\frac{F}{A}$
$\implies F=PA$
We plug in the known values to obtain:
$F=108MPa\times 4\pi R_{\circ}^2$
$F=108\times 10^6\times 4(3.1416)\times (0.609)^2$
$F=503MN$
