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6) Katara Unlimited started year two with Accounts Receivable of $500. During year two Katara collected $6,000 from its customers. At the end of year two, Katara had an Accounts Receivable balance of $700. What were Katara's sales on account during the year? a) $6,200 b) $5,800 c) $6,000 d) $7,100