Hello it's basic question but the tough part he needs 7 ways or methods and must be creative

You are now in college. You have moved into an apartment that you share with your two roommates. The electric bill for the month shows up in the mail. The bill is for $100. How will you determine how much you and your roommates should pay towards the bill? Come up with seven methods of determining who should pay what portion of the bill. Be very creative. Identify the best option. Why is it the best option