What is the 90% confidence interval for the mean sysbp values? First try using commands like: mean(fram$sysbp) sd(fram$sysbp) qt(0.05, df =46) sqrt(46) to calculate the confidence interval like you would from the hand calculation. Then try using the t.test() command with conf.level = 0.90 Does the confidence interval contain the population mean value of systolic blood pressure used in the null hypothesis? Is this consistent with the results of your hypothesis test? Why are we comparing a 5% significance level hypothesis test to a 90% confidence interval instead of a 95% confidence interval?