LSG Company is a calendar year, cash basis taxpayer. On November 1, 2015, LSG paid $9,450 cash

Question:

LSG Company is a calendar year, cash basis taxpayer. On November 1, 2015, LSG paid $9,450 cash to the janitorial service firm that cleans LSG’s administrative offices and retail stores. How much of this expenditure can LSG deduct in 2015 assuming that:
a. The expenditure is a prepayment for six months of cleaning services from November 2015 through April 2016?
b. The expenditure is a prepayment for 18 months of cleaning services from November 2015 through April 2017?