Prescription Terminology Identifying Evening Abbreviations

Which abbreviations indicate the prescription is taken in the evening?
Check all that apply.

a. hs
b. am
c. pm
d. pc
e. po

In regards to acetyl coa in the tca/kreb's cycle: how many cycles minimum would it take for an acetyl coa carbon to be removed? (what is the first step that this removal could happen? why can't we know for sure how many turns it takes?