Alpha Co

A department of Alpha Co. incurred the following costs for the month of September. Variable costs, and the variable portion of mixed costs, are a function of the number of units of activity:
Activity level in units 5,500
Variable costs $ 9,700
Fixed costs 31,000
Mixed costs 20,500
Total costs $61,200
During October the activity level was 8,500 units, and the total costs incurred were $71,500.
(a) Calculate the variable costs, fixed costs, and mixed costs incurred during October. Do not round your intermediate calculations.
Variable cost $
Fixed cost $
Mixed cost $

(b)Use the high–low method to calculate the cost formula for mixed cost. (Do not round your intermediate calculations. Round your answers to 2 decimal places.
Cost formula = $ + $ per unit