Assume that a company provided the following cost formulas for three of its expenses (where a refers to the number of hours worked): Rent (fixed) Supplies (variable) Utilities (mixed) $3,000 $4.009 $150 + $0.759 The company's planned level of activity was 2,170 hours and its actual level of activity was 1,850 hours. How much supplies expense would be included in the planning budget? Multiple Choice $8.00 $8,380 O $8.500 $8.680