For a random sample of 20 dairy cows, here are the number of pounds of milk produced during their first lactation (after the first calf) and their second lactation (after the second calf).

Cow First Lactation Second Lactation Cow First Lactation Second Lactation 1 22,792 29,655 11 15,058 8,013 2 31,693 23,817 12 16,681 23,301 3 18,367 35,360 13 21,002 32,529 4 17,440 21,848 14 17,987 23,620 5 29,798 29,828 15 15,968 26,437 6 28,540 33,898 16 23,580 26,227 7 23,661 22,444 17 14,334 25,529 8 39,242 23,648 18 24,030 27,368 9 21,574 25,303 19 20,392 29,527 10 34,542 34,812 20 24,347 25,592