A quality engineer wants to compare pistons from two suppliers. The engineer measures the lengths of a random sample of 100 pistons from each of the suppliers (A and B). A box plot of the results is found below. Which of the following statements is NOT correct? a) There are no statistical differences between suppliers. b) There are no practical differences between suppliers. c) Supplier A would be a better supplier. d) Both Supplier A and B exhibit a normal distribution