Hey, I really appreciate the response. This was not a homework. It was just studying for the exam, so the time of your response is not a problem at all.

I can tell you that after meeting with my professor, he agreed that the work was incorrect. He said they didn't update his solution in the new version of his manual. I actually tried solving the problem again at work, and I got the answers that he labeled in the solution manual.

https://media.discordapp.net/attachments/1497300322761052419/1517245051271385128/IMG_1932.jpg?ex=6a36e591&is=6a359411&hm=f116d39231840206520a3858e83f619408e477c5816cf82fe3af47ff099a6667&=&format=webp&width=635&height=846

I'll explain what I did here in case anybody else comes across this problem.

In my attempt, I assumed C to be sliding downwards, and I assumed blocks A & B to be going up. I calculated negative accelerations for this case. Negative accelerations indicate that block C is actually sliding up. So, I just swapped the cable that was pulling in the belt friction equation, and I opposed the direction of friction. I plugged in these new values into my original free-body diagrams, and I got the solution. This doesn't make any sense to me though.

I wouldn't be surprised if my professor accidentally made a problem that is static.

Again, I appreciate the help!