Exercise 10-18 a The Dinkle and Frizell Dental Clinic provides both preventive and orthodontic dental services. The two owners, Reese Dinkle 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 2020 is shown below. Difference from Budget Actual $39,400 $1,140 Favorable 4,960 4,130 1,820 2,590 480 Service revenue Variable costs: Filling materials Novocain Supplies Dental assistant wages Utilities Total variable costs Fixed costs: Allocated portion of receptionist's salary Dentist salary Equipment depreciation Allocated portion of building depreciation Total fixed costs Operating income (loss) 100 Unfavorable 110 Unfavorable 410 Favorable -0- Neither Favorable nor Unfavorable 100 Unfavorable 100 Favorable 13,980 3,180 9,710 6,150 14,990 34,030 $(8,610 ) 210 Unfavorable 460 Unfavorable -0- Neither Favorable nor Unfavorable 1,260 Unfavorable 1,930 Unfavorable $690 Unfavorable In addition, the owners know that the investment in operating assets at the beginning of the month was $81,560, and it was $ 73,210 at the end of the month. They have asked for your assistance in evaluating their current performance reporting system. Prepare an investment center responsibility report for the Preventative Services segment for May 2020. (Round ROI to 1 decimal place, e.g. 1.5%.) DINKLE AND FRIZELL DENTAL CLINIC Preventive Services Responsibility Report For the Month Ended May 31, 2020 Difference Favorable F Unfavorable U Neither Favorable nor Unfavorable N Budget Actual Contribution Margin Controllable Fixed Costs Controllable Margin Dental Assistant Wages Dentist Salary Equipment Depreciation Filling Materials Gross Profit Novocain Other Fixed Costs Service Revenue Supplies Total Controllable Fixed Costs Total Variable Costs Utilities Variable Costs Allocated Portion of Receptionist's Salary Allocated Portion of Building Depreciation Return on investment