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You are given the following data for Skylar Ltd.: Direct Labour Hours Overhead Costs 25700 $630800 January 32600 $700100 February 45117 $887306 March 37500 $720500 April 40349 $909220 May 21235 $624133 June July 23700 $651000 August 39200 $759000 September 41884 $751261 October 23082 $614932 November 25200 $620100 December 30100 $682000 Using the high-low method, what is the variable overhead cost per direct labour hour? Select one: a. $11.02 b.517.04 c. $6.16 d. 512.32