Answer
Please see the work below.
Work Step by Step
We know that
$F=mg$
$F=(4680)(9.8)=45864N$
$D=42.6cm=0.426m$
Now $A=\frac{\pi D^2}{4}=0.1425m^2$
We can find the pressure as
$P=\frac{F}{A}$
We plug in the known values to obtain:
$P=\frac{45864}{0.1425}$
$P=322KPa$