Question 820339
Assign some variables.
L = load
d = diameter
h = height


The description would give {{{L=kd^4/h^2}}} where k is a proportionality constant.


Next you are given some values and need to find the value for k.
{{{L*h^2/d^4=k}}},
Substitute the values for finding k,
{{{k=6*10^2/2^4}}}
and use this value for k in the question about L for the 3 foot diameter, 18 foot high column.