1.4 4. Lengths of Phone Calls, Part 11 As in the previous exercise, suppose the lengths of phone calls to the receptionist of a small company are i.i.d. with a mean of 5 minutes and an SD of 8 minutes. Let X1,X2, . . .,Xn be the lengths of 71 calls in minutes, and let A\" = Tl: 21:1 X!- be the sample average length. 2 In each of the following parts, either nd the chance exactly, or approximate it, or bound it. Do the best you can with the information given. a) P(|A15 _ 5|