These are not standard acronyms and certainly not acronyms that will be used in the exam.
I can only assume that you are referring to the discount factors, in which case the formulae are given in the exam at the top of the discount tables (and most times you do not need the formulae anyway because you will be using the tables that are given).
Have you not watched my free lectures covering this? The lectures are a complete free course for Paper MA and cover everything needed to be able to pass the exam well.