Find a decent used road bike. Put some clip on aerobars on it for the triathlon. (and training for the triathlon) If you're riding it around a college campus, you don't want to put too much money into because it will only stand out for getting stolen.
Lots of good late 80's, early 90's bikes can be had under $250. That leaves money for a TT helmet, trisuit, aero bars. And the bike won't stand out as a theft target.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.