Risk management & insurance question:

You are considering business income coverage for your business. You have determined that the longest potential shut down you expect to have is 3 months. Further, you have determined that September is the month with the largest business income exposure. The exposure for September is $7,000. The exposure for every other month is only $2,000 (each). If you decided to use the Monthly Limit of Indemnity option, what fraction would you choose, and what limit would you choose?