BGN and END mode (TI BAII Calculator)

CFA Level I FRA
#1

I’m getting used to financial calculators, reason of my silly question:

I’m supposed to use the BGN function only when explicitly the problem says “at the beginning of…”, if nothing its said I should always consider de CFlow at the end of the period (END mode on the calculator)… I’m ok? indecision

Thanks a lot!

#2

Yes. Or “starting today” etc.

#3

txs!