The comparative balance sheets for Riverbed Corporation show the following information. December 31 2017 2016 Cash Accounts receivable Inventory Available-for-sale debt investments Buildings Equipment Patents $33,600 $13,000 12,100 10,000 12,2009,000 03,000 -030,000 45,100 19,900 5,100 6,300 $108,100 $91,200 Allowance for doubtful accounts Accumulated depreciation-equipment Accumulated depreciation-building Accounts payable Dividends payable Notes payable, short-term (nontrade) Long-term notes payable Common stock Retained earnings $3,100$4,500 2,000 4,500 06,000 5,1003,000 -05,000 3,0004,100 31,000 25,000 43,00033,000 20,900 6,100 $108,100 $91,200