Dynamics Question-Motion on Inclined Plane

[wildareal]

A body of mass 25kg rests in limiting equilibrium on a plane 30 degrees to the horizontal. If the plane is raised until it is at an angle of 60 degrees to the horizontal, find:

a) the least force acting up the plane required to keep the mass in equilibrium.
b) the horizontal force required to keep the body from slipping down the plane.

[Mao]

In limiting equilibrium at 30 degrees, static friction is at its max. Use this information to determine the coefficient of friction.

For the new system at 60 degrees, the coefficient of friction has not changed. Find the force up the plane to keep the net force at zero (part a). For part b, imagine a force is horizontally applied to the body (as opposed to parallel to the inclined plane), find the magnitude of this force to keep the net force at zero.

See if you can take it from there, I'll come back in a couple of hours and finish this off if it is needed.