Problem $4\mathrm{.}79$ from Beer & Johnston using a force triangle. $($note solution is not in back of text and is $($a$)P=83\mathrm{.}2lb,($b$)P=66\mathrm{.}3lb).$ Hint: For part $b,={}_k$ because it is moving.

$4\mathrm{.}79$ Determine the smallest value of $P$ required to $($a$)$ start the block up the incline,

$($b$)$ keep it moving up$.$