Two blocks $\backslash ($ A $\backslash )$ and $\backslash ($ B $\backslash ),$ each having a mass of $7\mathrm{.}5$ kg $,$ are connected by the linkage shown in $($Eigure $1).$

igure

$1$ of $1$

Part A

If the coefficient of static friction at the contacting surfaces is $\backslash (\backslash$mu$\_\{\backslash$alpha$\}=0\mathrm{.}5\backslash ),$ determine the largest vertical force $\backslash ($ P $\backslash )$ that can be applied to pin $\backslash ($ C $\backslash )$ without causing the blocks to move. Neglect the weight of the links.

Express your answer to three significant figures and include the appropriate units.