The operations manager of a plant that manufactures tires wants to compare the actual inner diameters of two grades of tires, each of which is expected to be 575 millimeters. Samples of five tires from each grade were selected, and the results representing the inner diameters of the tires, ranked from smallest to largest, are shown below. Complete parts (a) through (c) below.

Grade X Grade Y 564 573 572 575 576 576 578 580 586 581