4. Cal's son is studying in the MBA program at UMGC. He tells his father that prot maximization 0: when marginal cost (MC) = marginal revenue (MR). Cal understands that his marginal cost is the sa his variable cost, or $2.158 per gallon. Technically, marginal cost is the added cost from selling one gallon. Cal asks you for a chart to show how prots vary with sales volume, assuming that he sells an addi1 400 gallons for each 10 cent decrease in price. Also, he wants to know by how much he can lower without losing money. Given that you know the price and quantity of gallons sold so far, and that Cal's cost per gallon is $1 per gallon and his xed cost is $438 per day, complete the table to the right