Joe's Tax Service provides professional accounting and tax services. All tax return services are classified into one of three categories: standard, multiform, and complex. Following is information for last year. Also, last year, the fixed cost of rent, utilities, and so forth were $70,000. Standard Multiform Complex $145 $270 Billing rate Average variable costs Average contribution margin Number of returns prepared 1,750 $70 (30) $40 (75) (150) $70 $120 500 250 Required (a.) Determine Joe's break-even dollar sales volume. (b.) Determine Joe's margin of safety in sales dollars.