Originally Posted by
superdex
5. It will be hard enough.
Master 45+ will be 'open' which means you'll be blown off in just a few laps.
A lot of races will let you sign up for multiple, so there's no harm in doing both, though if the Master's is first you may be too toasted for another race.
That's what I was going to suggest, especially if the Masters race is later in the day. Just race that one for experience and fitness. Your goal will be to stay attached for as many laps as possible.