An investigator theorizes that people who participate in regular exercise will have levels of systolic blood pressure that are significantly different, higher or lower, from that of people who do not participate in regular exercise. To test this idea, the investigator randomly assigns 21 subjects to an exercise program for 10 weeks and another 21 subjects to a non-exercise comparison group. After ten weeks, the mean systolic blood pressure of the subjects in the exercise group is My = 127 and the standard deviation is S1 = 10. In the non-exercise group, the mean is My = 137 and the standard deviation is s2 = 9.0. Please test the investigator's theory using an alpha level of 0.05, two tailed. 1. What is the pooled variance? s2p= 2. What is the r-statistic for the sample mean difference? 3. How many degrees of freedom are there for this test? df= 4. Is the critical y-stay for alpha 0.5 two-tailed is 2.021, is the result significant? I need help solving these questions with an explanation please! Thank you