This is a theory question. Let's say I go down a slope on my skis. When I want to calculate the Work done by air resistance, do I take the angle of the slope in consideration?

For example, will it be: Wr = -Fr * d * sinTHETA

or will it only be Wr = -Fr * d

Thank you

same thing with kinetic friction. I have a question where they ask me to find the work done by friction between the skis and the snow. my answer is:

Wf = -Fc * d, but I have a feeling that I need to add the angle to it, or is that only with gravity?