Part B (Short Answers) Please answer concisely and note the word limits. Question 21: Fred used the formula m + to/2(Sm) to estimate the mean income of Canadian adults from a (3 Points) random sample of 10 Canadian adults. Why is this confidence interval almost certainly invalid? Words: 0 / 50 Question 22: When do we use za/2 and when do we use ta/ to compute a confidence interval around a ere to search O W P T 24OF e