Part A: An attached stem and leaf plot is provided. A nonsplit system was applied for the stem and leaf plot to facilitate clearer analysis. Part B: The shape of the stem and leaf plot indicates an average rise in pulse rate of 20 beats across all 19 students post-exercise. There is minimal shape variation between the pre- and post-exercise plots, with only a small decrease of one in the third last row and an increase of one in the second last row of students. The distribution patterns were consistent in both scenarios, with the majority of students in the 60s range before exercise (7 students) and the 80s range after exercise (8 students). Step-by-step explanation: The provided data is as follows: 67, 87, 67, 88, 67, 89, 68, 89, 71, 91, 72, 93, 72, 93, 75, 95, 77, 96, 77, 97, 79, 98, 81, 98, 85, 101, 87, 105, 87, 105, 91, 119, 97, 125, 103, 125, 121, 147.
Answer: There exists a distinction between rote counting and rational counting. Rote counting requires memorizing sequences of numbers, whereas rational counting informs children about "how many items there are." For children to engage in rational counting, they must exhibit one-to-one correspondence.
