Problem 18-1A (Algo) Measuring costs using high-low method LO P1 [The following information applies to the questions displayed below.] Alden Company's monthly data for the past year follow. Management wants to use these data to predict future variable and fixed costs. Problem 18-1A (Algo) Part 1 . Estimate both the variable costs per unit and the total monthly fixed costs using the high-low method. (Do not round intermediate alculations.)