Oriole Corp. has collected the following data concerning its maintenance costs for the past 6 months. Units Produced Total Cost July 15,840 $31,680 August 28.160 42,240 September 31,680 48,400 October 19,360 33,440 November 35,200 65,560 December 33,440 54,560 (a 1) Compute the variable cost per unit using the high-low method. (Round answer to 2 decimal places, eg: 2.25.) Variable cost per unit $