Mark owns a machine shop. In reviewing the shop's utility bills for the past 12 months, he found that the highest bill of $2,600 occurred in August when the machines worked 1,200 machine hours. The lowest utility bill of $2,300 occurred in December when the machines worked 600 machine hours. Requirements 1. Calculate the variable rate per machine hour and the total fixed utility cost. 2. Show the equation for determining total utility cost for the machine shop. 3. If Mark anticipates using 800 machine hours in January, predict the shop's total utility bill using the equation from Requirement 2 Requirement 1. Calculate the variable rate per machine hour and the total fixed utility cost. First, calculate the variable rate per machine hour. Select the formula labels, then enter the amounts and compute the variable rate per machine hour. (Use the high-low method. Round your answer to the nearest cent.) Variable rate per machine hour