14000 is incorrect

Dustin has a contract to provide services to Dado Enterprises. In November of this year, Dustin billed Dado $14,000 for the services he rendered during the year. Dado is an accrual-method proprietorship that is owned and operated by Dustin's father. What amount can Dado deduct this year assuming Dustin uses the cash method and Dado remits payment for the services in January of next year