Comparative income statements for Tudor Retailing Company for the last two months are presented below:

SeptemberOctoberSales in units5,0007,000Sales revenue$100,000$140,000Cost of goods sold40,00056,000Gross margin60,00084,000Selling and administrative expenses:Shipping expense7,50010,500Clerical expense10,00012,000Maintenance expense17,00017,000Total selling and administrative expense34,50039,500Net operating income$25,500$44,500

If the Tudor Retailing Company uses the high-low method of analysis, the total monthly fixed cost for Tudor Retailing Company would be estimated to be: