a. Find the cubic function that is the best fit for the data in the table below. b. Find the quartic function that is the best fit for the data in the table. X 2 3 4 5 6 7 - 12 - 2 0 4 50 175 1500 . . . . . a. The cubic function is y = (Simplify your answer. Use integers or decimals for any numbers in the expression. Round to three decimal places as needed.) b. The quartic function is y = (Simplify your answer. Use integers or decimals for any numbers in the expression. Round to three decimal places as needed.)