8. A researcher wishes to compare the effect of two stepping heights (low and high) on heart rate aerobics workout. The researcher constructs a 98% confidence interval for the difference in mean heart...

I know the answer to 8 but had to include it to get help with question 10.  Thanks.

Extracted text: 8. A researcher wishes to compare the effect of two stepping heights (low and high) on heart rate aerobics workout. The researcher constructs a 98% confidence interval for the difference in mean heart rate between those who did the high and those who did the low stepping heights. Which of the following is a correct interpretation of this interval? (A) 98% of the time, the true difference in the mean heart rate of subjects in the high-step vs. low-step groups will be in this interval. (B) We are 98% confident that this interval captures the true difference in mean heart rate of subjects like these who receive the high-step and low-step treatments. (C) There is a 0.98 probability that the true difference in mean heart rate of subjects in the high-step vs. low-step groups in this interval. (D) 98% of the intervals constructed in this way will contain the valuę 0. (E) There is a 98% probability that we have not made a Type i error. a step-


Extracted text: 10. The researcher in question 8 randomly assigned 50 adult volunteers to two groups of 25 subjects each. Group 1 did a standard step-aerobics workout at the low height. The mean heart rate at the end of the workout for the subjects in group 1 was 90 beats per minute with a standard deviation of 9 beats per minute. Group 2 did the same workout but at the high step height. The mean heart rate at the end of the workout for the subjects in group 2 was 95.2 beats per minute with a standard deviation of 12.3 beats per minute. Assuming the conditions are met, which of the following could be the 98% confidence interval for the difference in mean heart rates based on these results? (A) (2.15, 8.25) (B) (-0.77, 11.17) (C) (-2.13, 12.54) (D) (-2.16, 12.56) (E) (-4.09, 14.49)