Thomas Train has collected the following information over the last six months. Month Units produced Total costs March 10,000 $25,600 April 12,000 26,200 May 18,800 27,600 June 13,000 26,450 July 12,000 26,000 August 15,000 26,500 Using the high-low method, what is the variable cost per unit? Round to two decimal places.