The Sheffield and Frizell Dental Clinic provides both preventive and orthodontic dental services. The two owners, Reese Sheffield and Anita Frizell, operate the clinic as two separate investment centers: Preventive Services and Orthodontic Services. Each of them is in charge of one of the centers: Reese for Preventive Services and Anita for Orthodontic Services. Each month, they prepare an income statement for the two centers to evaluate performance and make decisions about how to improve the operational efficiency and profitability of the clinic. Recently, they have been concerned about the profitability of the Preventive Services operations. For several months, it has been reporting a loss. The responsibility report for the month of May 2022 is shown here. Actual Difference from Budget $39,470 $1,050 Favorable Service revenue Variable costs Filling materials 5,090 150 Unfavorable Novocain 3,930 140 Unfavorable Supplies 1.970 370 Favorable Dental assistant wages 2,450 -0- Neither Favorable nor Unfavorable. Utilities 500 80 Unfavorable