6. Consider the following data set of reflecting the amount of money spent monthly on phone apps by people that do tend to purchase phone apps monthly. Men Women 42 46 63 35 41 41 48 59 66 34 53 60 48 60 46 78 64 90 58 66 Use the Mann-Whitney test to determine if there is a difference in population means at 95% confidence 7. Consider the combined data in the preceding question above. (a) Predict at 90% confidence the value of the population standard deviation for this combined data set. Verify your results with Minitab outputs. (b) Test at 95% confidence if the value of the population standard deviation is over 8.00?' Verify your results with Minitab outputs. (c) Test at 90% confidence if the value of the population standard deviation is under 12.25? Verify your results with Minitab outputs. 8. For the above data, test if the population variances are equal or not at 90% confidence and then perform the appropriate test of difference of means using p-values. Verify your results with Minitab outputs