Grohs Kennel uses tenant-days as its measure of activity; an animal housed in the kennel for one day is counted as one tenant-day. During December, the kennel budgeted for 2,500 tenant-days, but its actual level of activity was 2,530 tenant-days. The kennel has provided the following data concerning the formulas to be used in its budgeting: Revenue Wages and salaries Food and supplies Facility expenses Administrative expenses Fixed Element per Month $ 0 Variable element per tenant-day $ 33.00 $ 3,800 $.7.90 1,000 11.60 8,600 2.20 6,200 0.20 $ 19,600 $ 21.90 Total expenses The net operating income in the planning budget for December would be closest to: