Ball Positioning on penalty

[Fedex]

Ok...3rd year official here. I have been selected to a varsity crew as an umpire. I have really only worked the wings and back judge, so this will be new to me. Here's the situation. 1st and 10 from A's 35. The ball is positioned right in between the hashmarks. A33 takes the pitch and runs right for 5 yards OOB to A's 40. During the play, the TE A81 holds at A's 38. This hold occurred right on the right hashmark. B accepts the penalty. Now, my question is this: Is the penalty marked off from the hashmark (Where the foul occurred) or is it marked off from where the ball was previously spotted (between the hashmarks)?

Thanks for the help. Any other advice you guys can give to a new U? I know about the Snicker's bars, but I am slender and speedy so I think I'll skip the candy bars.