For each transaction below, calculate the amount of revenue to be recorded in the current period using accrual-basis accounting: Required: a. Performed $29,000 of services during the month and received full cash payment from customers at the time of service. b. Performed $4,000 of services during the month and billed customers. Customers are expected to pay next month. c. Received $15,000 cash from customers for services to be provided next month.