5. (10pts) To evaluate the performance of classifiers C1 and C2 on the same dataset D, we conduct five-fold cross-validation, which gives the F-measures of five folds as follows C1: 0.8, 0.7,0.75, 0.81, 0.85 C2:0.75, 0.75, 0.7, 0.8, 0.88 Compute the means and "error bars" for each classifier. Can you assert which classifier performs statistically significantly better at the confidence level of 95%, and why