I recognised the reference to 'Keep Calm and Carry On' - available on mugs near you - but still don't see what FGZstar means. I'm happy to accept that it's just a generational thing.
Datum and agendum are singular. One singular piece of data and one singular thing to do, rather than a list. The minute it is two (or more) they become data and agenda. So, "What's on the agenda?" is correct being people are going to expect more than one item. If I say the only thing on the agenda is the meeting, that's wrong, it's the agendum. Yes, I am just being a grammar nazi. I don't really care that much about those words.
[INJ} I am given to understand by today's youth that "to bail" would indicate giving up in a dramatic way. It would appear to come from "bailing out (of an aeroplane)". Incidentally, "Keep Calm and Carry On" is available on a mug in my own kitchen.