Sunland Corp. has collected the following data concerning its maintenance costs for the past 6 months. Units Produced 16,920 July Total Cost $33,840 45,120 August 30,080 33,840 51,700 20,680 35,720 September October November December 37,600 70.030 35.720 58,280 (a1) Compute the variable cost per unit using the high-low method (Round answer to 2 decimal places, eg, 2.25.) Variable cost per unit $ $