Taha Company is developing a cost function for its total costs using the high-low method. The following cata have been collected for the past year: Quarter Total Costs 5,000 $ 745 1 2 6,500 820 3 7,000 850 4 8,000 1,000 Calculate the following amounts: d. The variable cost per unit b. The fixed cost c. The estimated total cost for 9.000 units