Oriole, Inc., has collected the following information on its cost of electricity: Machine Hours Total Electricity Costs January 500 $250 February 540 $280 March 340 $160 April 470 $220 May 680 $240 June 710 $330 July 330 $160 August 500 $280 September 240 $128 October 770 $330 November 870 $380 December 600 $320 (a) Identify the high and low points. High point Low point Machine Hours Using the high-low method, compute the variable cost of electricity per machine hour. (Round unit cost to 2 decimal places, es. 52.75.) Variable cost $ per machine hour