The following are three data sets for Cu content (mg kg-) in black tea leaves from Cameron Highlands. Data Set 1 26.5 27.0 27.6 25.6 Data Set 2 25.4 26.4 27.6 27.3 Data Set 3 27.4 25.6 25.1 (i). Calculate the 95% confidence level of Data Set 1 and Data Set 2. (ii). Apply ttest to determine whether the mean of Data Set 1 is identical of to that of Data Set 3 at 95% confidence level. (Spooled = 1.013 mg kg-)