The balance in Accounts Receivable at the beginning of the period amounted to $3,600. During the period $6,800 of credit sales were made to customers, and uncollectible accounts expense amounted to $440. The ending balance in Accounts Receivable is $1,400, and the ending balance in the uncollectibles allowance account is $600. The amount of cash inflow from customers that would appear in the operating section of the statement of cash flows is