We're not here to do your work for you.
If you've got a problem understanding the assignment, ask your teacher. That way, they know the problem has to be described better.
I have no idea what you're not understanding, but the not so clear part is if there is a tie between students scores, they get the same rank, but skip the number of ranks equal to the number of tied students. Like this:
Rank Student Score
1 10
2 9
2 9
2 9
5 8
6 7