Maybe that picture will help?

Along the plane:

Ff is the force due to friction,

mg sinθ is the component of weight,

T is the tension.

Perpendicular to the plane:

mg cosθ is the component of weight,

R is the normal reaction force.

Perpendicular to the plane, we don't have any net force (or the log would sink into the ramp, or jump over it), hence R = mg cosθ

Along the plane, we have the tension T being the largest of all the forces.

T - mg sinθ - Ff = ma

You will have to realise that θ = 30 degrees

And that Ff = μR = μ(mg cosθ)

[μ - coefficient of friction]

So that:

T - mg sinθ - μ(mg cosθ) = ma

For the second problem, you will have to be careful about the direction of the force; whether it is along the plane or at the horizontal, or at any other angle to the horizontal. Since you didn't mention anything about that, I would assume it's along the plane, and the easier way of the different possibilities. It would be like the mirror image of the picture I posted above, with only the mass and angle changing, and a force F instead of the tension T.