$(5-8).$ The $20-kg$ block in Fig. P$5-8$ rests on a $30$ incline. Knowing that ${}_s=0\mathrm{.}25,$ determine the magnitude and direction of the smallest force

$P$ required to cause the block to start sliding

up the incline.

$(5-9).$ From Problem $5-8,$ determine the magnitude and direction of the smallest force $P$ required to prevent the block from sliding down the incline.

FIGURE P$5-8$