A $160-$lb block is pulled up by a constant force $P$ through a cable to move up the inclined surface with a constant acceleration of $a=8f\frac{t}{s^2}.$ The coefficient of kinetic friction between the block and the inclined surface is ${}_K=0\mathrm{.}25.$ The angle between the cable and inclined surface as shown is $=42.$ Neglect size of the block,

A$)$Determine the magnitude of the force P applied on the cable.

B$)$ determine the normal force N exerted on the block from the inclined surface

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