A supervisor is reviewing a production line that has been experiencing problems with the sequencing of tasks. The problem is that gridlocks are occurring because of the inconsistency of sequential operations. He decides to conduct a test wherein two different techniques are used to finish the same task. He measures the times (in minutes). From the sample data he calculated some relevant information given below: Standard Sample Averages Deviation Size Ex ExA ExB Ex's Technique A 13.3 4.99 10 133 1993 Technique B 14.5556 5.5927 9 131 2157 a) Can the supervisor conclude that technique A is more consistent than technique B? Use 95% confidence. b) Estimate the variability of technique A with 90% confidence. c) (Fill in the blanks - this question is independent of a) and b)) A random sample of size n is drawn from a population that is normally distributed whose standard deviation is o . In hypothesis testing for the population mean, the t test should be used instead of the z test if n is greater than and o is