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: Averages Standard Deviation Sample Size Z*A Ex? ExB Technique A 20.8 16.9365 10 208 6908 Technique B 14.5556 5.5927 9 131 2157 a) Can the supervisor conclude that technique A is less consistent than technique B? Use 97.5% confidence. b) Estimate the variability of technique B with 95% confidence. c) (Fill in the blanks) 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