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 $10,450

Fixed costs $33,000

Mixed costs $18,620

Total costs $69,000

During October the activity level was 8,200 units, and the total costs incurred were $69,000.

a. Calculate the variable costs, fixed costs, and mixed costs incurred during October.

Variable Cost $15,580

Fixed Cost 33,000

Mixed $20,420

b.Use the high-low method to calculate the cost formula for mixed cost. (Do not round intermediate calculations and round your answers to 2 decimal places.)

Cost Formula __________ + ___________ per unit