PHYSICS
posted by Shereen on .
A crate of potatoes of mass 23.0 kg is on a ramp with angle of incline 30° to the horizontal. The coefficients of friction are μs = 0.65 and μk = 0.44. Find the frictional force (magnitude and direction) on the crate if the crate is at rest.
Please help with detailed solution I need to find the magnitude and the direction (up or down ramp)

force friction= mu*forcenormal
= mu* mg sinTheta
IF gravity is downward on the ramp, then fricion is upward.
http://www.physics247.com/physicshomeworkhelp/slope.php 
what is mu equal to?