2.49 Consider the following four populations:

• 2, 3, 4, 5, 5, 6, 7, 8

• 1, 1, 1, 4, 5, 7, 7, 14

• 2, 4, 4, 5, 5, 8, 8, 4

• -9, -3, 0, 3, 9, 12, 13, 15 All these populations have the same mean. Without doing the calculations, arrange the populations according to the magnitudes of their variances, from smallest to largest. Then calculate each of the variances manually.