Kirnon Clinic uses client-visits as its measure of activity. During July, the clinic budgeted for 2,000 client-visits, but its actual level of activity was 2,010 client-visits. The clinic has provided the following data concerning the formulas to be used in its budgeting: Fixed element per month Revenue Personnel expenses Medical supplies Occupancy expenses Administrative expenses Total expenses $ 26,100 1,000 6,800 3,000 $ 36,900 Variable element per client-visit $ 43.70 $ 12.10 6.30 1.60 0.20 $ 20.20 The activity variance for personnel expenses in July would be closest to: Multiple Choice $901 F $121 F $901 U $121 U