2. A certified mechanic was timed for the repair of an automobile on 14 separate occasions. Over the same period a trainee mechanic was timed for the repair of a similar automobile. The times in...

Do part c of question two *only*!!!! Please.

Extracted text: 2. A certified mechanic was timed for the repair of an automobile on 14 separate occasions. Over the same period a trainee mechanic was timed for the repair of a similar automobile. The times in minutes are given below Certified 344276 257 334| 267 | 164 | 222 343 212 175 211 311 | 209 | 188 Trainee 222 342 178 234 398 232 377 211 309 190 351 343 177 269 a. Calculate a 99% confidence interval for the mean time taken to repair the automoble by the (i) certified mechanic and (ii) the trainee mechanic. b. Test the hypothesis that the two mean times for both mechanics are equal. Use the 5% level of significance. c. Subsequently, it was learnt that the times for he trainee were incorrecly recored and that each of the values above is 30 minuetes teoo small. What, if any, differencr soes this make to the results of the test done in part (d)?