The manager of Handy Car Inspection reviewed the monthly operating costs for the past year. The costs ranged from $4,300 for 1,300 inspections to $3,900 for 900 inspections Read the requirements. Requirement 1. Use the high-low method to calculate the variable cost per inspection. Select the formula and enter the amounts to calculate the variable cost per inspection. (Round to the nearest cent.) Variable cost per inspection: Requirement 2. Calculate the total fixed costs. Select the formula and enter the amounts to calculate the total fixed costs. (Use the highest volume and its mixed cost to calculate the total fixed cost.) Total fixed cost Requirement 3. Write the equation and calculate the operating costs for 1,200 inspections Select the formula and enter the amounts to calculate the operating costs for 1,200 inspections. (Enter all amounts to the nearest cent.) Total mixed cost