2. Machine hours and electricity costs for AMK Industries for the past year were as follows: Month Machine Hours Electricity Costs January 2,000 $18,900 February 2,400 21,500 March 1,400 14,000 April 2,600 23,500 May 3,300 28,750 June 3,300 22,700 July 3,600 25,250 August 3,000 23,250 September 1,500 16,000 October 3,300 26,500 November 4,200 31,500 December 4,200 22,250 Required: a) Using the high-low method, develop a cost function for monthly electricity costs. (10 Marks) b) Using the regression analysis method, develop a cost function for monthly electricity costs (20 Marks) c) Determine the r' of the distribution and comment on the use of machine hours as a basis for the estimation of electricity costs. (6 Marks) d) Estimate electricity costs for a month in which 1,300 machine hours are worked. (4 Marks) Total (40 Marks)