$(35$ points$)$ Block $A(75$ kg ; green$)$ sits on top of block $B(150$ kg ; red$).$ Block $A$ is connected to the wall by link $L.$ The static friction coefficient between block A and $B$ and between block $B$ and the floor is ${}_s=0\mathrm{.}3.$ What is the largest force $P$ that can be applied before block $B$ starts moving? $($Result check: $P=882\mathrm{.}9N)$ What is the largest force $P$ that can be applied before block $B$ starts moving if link $L$ is removed? $($Result check: $P=662\mathrm{.}2$ N $)$

Use dry friction formulas