Then you can check this page for an example (the UBC Sprint triathlon in 2008):
http://www.winningtime.ca/08ubctri/triage.txt

The bike leg is 20 km and the terrain is not especially easy, often has a headwind on the uphill portion, as well as one short-steep hill (to be repeated twice). Some people show up on nice tri bikes, others on old rusty mountain bikes.

If you just want to finish, don't worry about speed and go for it!!