Below are the data collected from the products of three different machines. سا . Machine А B с n 9 7 9 Sample Art. Mean 48,3 60 43,7 Sample Variance 23,5 32,3 50,5 1- (15pts) Test whether , = 50 at a 95% confidence level. 2- (20pts) Test whether H = H, at a 95% confidence level. 3-