Florida Real Estate Practice Question

A business broker is reviewing the end-of-year balance sheet for a local property management firm. The firm currently holds $120,000 in cash and accounts receivable, and owns an office building valued at $400,000. On the other side of the ledger, the firm has $40,000 in unpaid short-term vendor invoices and a long-term mortgage balance of $250,000. If the broker is trying to determine the firm's working capital, what is the correct figure?