Inferential Statistics 1. Suppose the mean life of a battery If we observed a sample size of 50 and found out that the sample mean is 40 months with a margin error of 1.96. N= 50 ; Mean = Identify: Estimate = 95% confidence Interval = Interpretation. 2. Researchers In a certain medical center are Interested In assessing the effect of chronic ledthin use on total blood cholesterol. A sample of ten middle-aged men with hypercholesterolemia had their total cholesterol measured prior to and following six. month perlod regimen of lecithin Intake. The researchers would like to test whether the population mean blood cholesterol level changed significantly after prolonged lecithin used. a. What statistical treatment is applicable to the situation? Explain. b. State the null hypothesis. c. If the computed statistics is 1.38 with a p value of 0.20, what is your conclusion at 95% level of confidence