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Canyon Tours showed the following components of working capital last year: Accounts receivable Inventory Accounts payable Beginning $26.400 10,200 13,500 End of Year $20,300 12,800 18,300 a. What was the change in net working capital during the year? (Use the minus sign to enter negative changes, if any.) ANWC b. If sales were $37,800 and costs were $27,600, what was cash flow for the yedd> Ignore taxes (Use the minus sign to enter negative changes, if any.) Cash flow