Practical Question: (2 Marks) Lawson Lumber uses the highHow method to estimate electricity cost, which varies in relation to machine hours. The following data are taken from last year. Machine hours Electricity January 18,900 $122,850 February 16,800 $118,650 March 13,650 $118,125 April 10,500 $101,500 May 23,100 $116,550 June 25,200 $131,775 July 21,000 $126,000 August 18,900 $119,700 September 28,000 $154,000 October 11,550 $116,025 November 12,600 $119,175 December 14,700 $119,175 Required: Cost function for estimating electricity cost using high-low method. (Show all workings)