First,
I can't give an absolute answer to your first question, but I would expect that your written exam will correspond to your assignment. I've never heard of anyone getting an exam that didn't match their assignment.
As for what fields to display, the interface design is up to you. (It's a design
test, after all.) If I were using an online booking app I'd like to see the number of available seats, but that's just my preference. Most people seem to agree that you don't have to update the client when another user books a seat (check your assignment carefully - it probably addresses this question). If a user (based on stale data) attempts to book more seats than are available, however, the system certainly shouldn't let him.
Regarding your user name: If that's your real name, it's pretty cool. If not, please register your real first and last name - see
the JavaRanch naming policy for more details.
Thanks,
jply