Pool Perfection provided pool maintenance services worth $1,600 during July; in June, the customers had paid in advance for these services. During July, the company performed $1,000 of pool maintenance services, and in August, collected payment from those customers. Also, during July, the company accepted an order to perform $500 of pool maintenance services in August; the customers will pay for these services during August. The company uses accrual basis accounting. The Service Revenue account should be credited for: