Exercise 11.60 presented data (data set EX1160) on the heart rates for samples of 10 men randomly selected from each of four age groups. Each man walked a treadmill at a fixed grade for a period of 12 minutes, and the increase in heart rate (the difference before and after exercise) was recorded (in beats per minute). The data are shown in the table.

a. Do the data present sufficient evidence to indicate differences in location for at least two of the four age groups? Test using the Kruskal-Wallis H-test with α =.01.
b. Find the approximate p-value for the test in part a.

0.0 28 29 34 36 21 20 25 24 33 32 82 2233222233 2 5-37 25 22 33 28 26 30 34 27 33 95 24 27 33 31 21 28 24 34 21 32-75 1-29 33 2 2 3 3 33 2 32-09 953