Crane Inc. has collected the following information on its cost of electricity , Machine hours total electricity cost January 520 $230 February 540 $290 March 380 $190 April 450 $220 May 640 $260 June 700 $349 July 330 $170 August 540 $280 September 260 $114 October 750 $330 November 850 $350 December 600 $300 a. Identify the high and low points Machine hours High point $ Low point $ b. Using the high-low method compute the variable cost of eclectricity per machine hour. (round unit cost to 2 decimal places)