The vet card has a column in it for "Units": please enter "MI" or "KM" or "Cubits" or ... for your units and then you can be comfortable in leaving the math to others.
It's pretty easy to get the times. There are 4 of them for the US riders (or rather, for those people riding in one of the four time zones of the US).?
Eastern (EST) : 15:00 (3PM) Dec25 (Note: when you fill out your vet cards, you need to use "Military Time". None of this AM/PM stuff thank you very much. We can all count to 24!!
Central (CST): ?14:00 (2PM) Dec 25
Mountain (MST): 13:00 (1PM) Dec 25
Pacific (PST): 12:00 (NOON) Dec 25
There are, of course there are a large number of time zones in the world (68?) - And those that want a full list might want to add to the above.