Problem $3$:

Consider the figure below from Salgado $(2008).$

$($a$)$ Solve for the stress increase at point P using an elastic solution and only considering the load from the $\backslash (10\backslash$times $15\backslash$mathrm$\{$~m$\}\backslash )$ building.

$($b$)$ Solve for the stress increase at point P using an elastic solution, but now including the load from the $\backslash (7\backslash$times $25\backslash$mathrm$\{$~m$\}\backslash )$ building. What is the percent difference between the cases where you did, and did not include the effect of the second building?

$($c$)$ Solve for the stress increase at point $\backslash ($ P $\backslash )$ from both buildings using a simplified $2$:$1$ approach. What is the percent difference between the results obtained by these two methods?