LHJ Company collected the following production data for the past month: Units Produced Total Cost 1,600 $70,000 1,300 57,000 1,500 67,500 1,100 49,500 If the high-low method is used, what is the monthly total cost equation? a. Total cost $13,200 + $33/unit b. Total cost - $4,600 + $39/unit c. Total cost = $4,400+ $41/unit d. Total cost - $4,100+ $43/unit