Hot'lanta, Inc., which uses the high-low method to analyze cost behavior, has determined that machine hours best explain the company's utilities cost. The company's relevant range of activity varies from a low of 600 machine hours to a high of 1,100 machine hours, with the following data being available for the first six months of the year: Month Utilities Machine Hours January $9,900 920 February 9.560 840 March 10,150 930 April 10,560 1,040 May 10,779 1,070 June 10,350 1,020 The variable utilities cost per machine hour is: O $5.30. O an amount other than those listed above. O $0.19. $4.30. O $4.80