Unless I'm mistaken, the solution procedure should be similar to problem number 514 or something like that. A purely vertical load on the support leg of an "L-shaped" member. Don't have it in front of me now. Also this exact issue was brought up on the forum of another site. Quick google search should get you there.
Ok, I very fast realized you were referring to problem 514 from the old NCEES Practice Exam, before 2015 version, and I have the 2015. Luckily I also have the previous version!
Someone from this forum was very kind to send me their copy for studying purposes. (Thank you @joy21 ! )
Now, I would really like to get the errata for the previous version of the NCEES exam as I suspect problem 14 will have a correction as problem 509 does. Still a little in the dark about exactly how these problems should be solved, here is what I understand so far.
1. In an asymmetrical beam, "the bending axis passes through the shear center, not the centroid." (CERM 15th ed. Pg 45-17 - references will be from here-)
2. The torsional eccentricity is the distance between the shear force and the shear center. Therefore giving the torsion moment.
a.) The torsional moment is NOT the P*e base on the centroid of the asymmetrical member, but P*e based on the shear center and the distance to load P (or V for shear).
I still don't think they would make us calculate the shear center of an asymmetrical member, but Its just a wild guess. I really don't have any experience to back it up. So all in all, I think problem 514 also should be corrected since the solution is based on the centroid. But, I have in fact not passed my PE and have a lot to learn. I appreciate the help and can only ask for more. I will keep digging and googling.
Thanks,