PART ONE: INDEPENDENT T-TEST A researcher designs an experiment to evaluate the effect of high-salt dict versus low-salt diet on 1-year-old infants' systolic blood pressure (SBP). A total of 50 infants (25 infants in each diet group) was recruited and the SBP for each infant was measured in mm Hg. The researcher wants to know whether the mean of SPB among 1-yearold infants is different between high-salt diet and low-salt diet. We analyze the data using SAS's TTEST procedure and observe the results shown in Table 1 (see page 5). Based on those findings, answer the following questions. 1) Report and interpret the 95% confidence interval of the mean change of SBP among infants with highsalt diet and interpret the result. [Report fourth decimal places] 2) Identify the dependent variable and the independent or explanatory variable(s) in this study. Also, state the nondirectional Null and Alternative hypotheses. Page Break 3) An important step in an Independent t-Test is to first test for equal variance. Based on the information in the "Equality of Variances" portion of the output table, what is your decision about the Null hypothesis regarding equal variances (i.e. Ho: Variance, = Variance2)? In your answer, report the test statistic and P-value from the SAS output that you used to make your decision. 4 Now we want to test the Null hypothesis that was stated in Question 2. From the "T-Tests" portion of the output, report the test statistic, degrees of freedom (DF), and P-value that should be used to test the Null hypothesis. Based on that information, what conclusion can you make about the Null hypothesis (i.e. Reject or Fail to Reject the Null)? 5) Interpret these findings (3-4 sentences max). Your answer should (1) restate the findings, and (2) note the generalizability of these results.Table 1: Output for Part One Independent Group t-Test Example The TTEST Procedure Variable: SBP Group Method N Mean Std Dev Std Err Minimum Maximum High_sal 25 89.3379 8.8080 1.7616 69.6697 108.2 Low_salt 25 78.7514 6.4244 1.2849 68.6783 92.2177 Diff (1-2) Pooled 10.5865 7.7089 2.1804 Diff (1-2) Satterthwaite 10.5865 2. 1804 Group Method Mean 95% CL Mean Std Dev 95% CL Std Dev High_sal 89.3379 85.7021 92.9736 8.8080 6.8775 12.2533 Low_salt 78.7514 76.0995 81.4032 6.4244 5.0163 8.9373 Diff (1-2) Pooled 10.5865 6.2025 14.9705 7.7089 6.4286 9.6307 Diff (1-2) Satterthwaite 10.5865 6.1919 14.9811 Method Variances DF t Value Pr > It) Pooled Equal 48 4.86 <.0001 satterthwaite unequal equality of variances method num df den f value pr> F Folded F 24 24 1.88 0.1291