Draw a diagram of all the forces acting on block A.

[spriteboost]

Block A, with weight 3w, slides down an inclined plane S of slope angle 36.9 ∘ at a constant speed while plank B, with weight w, rests on top of A. The plank is attached by a cord to the wall (the figure (Figure 1) ).

Part A
Draw a diagram of all the forces acting on block A.
Draw the force vectors with their tails at the center of the block A. The orientation of your vectors will be graded. The exact length of your vectors will not be graded but the relative length of one to the other will be graded.

just stuck on this tried to do it i have vectors
fab friction between ab
fas friction between as
Nb Normal force by plank b
Ns Normal force by plane s
and Wa weight of block a

 

[Simon Bridge]

Welcome to PF;
You can attach pictures to a post - or just describe the diagram.
There is no a,b, or s in your description - did you mean those to be upper-case characters?
For each of the forces you have identified, have you figured out which direction they act?
(Hint: directions can be "up", "down", "along the plane", "perpendicular to the plane", and up or down in relation to the last two.)

 

[spriteboost]

opps sorry didn't upload a picture. Thought I did think I did it this time and I've tried a few different ways and marked me wrong.

 

[Simon Bridge]

Oh there you go - I was hoping you'd draw arrows on it.

curious: 36.5$^\circ$ is an odd angle ... 36$^\circ$ is $\small \pi/5$ radians.
I figure it's random.