Warren Company is a calendar year, cash basis firm. On December 6, 2018, Warren paid $7,200 cash to a landscape service business that maintains the lawns and gardens around Warren's headquarters. How much of this expenditure can Warren deduct in 2018 assuming that:

a. The expenditure is a prepayment for four months of landscape maintenance beginning May 1, 2019?

b. The expenditure is a prepayment for 12 months of landscape maintenance beginning May 1, 2019?