Q1.(i) The logistics department of a large firm employs three "estimators" whose job it is to decide the likely cost of delivering their products to their customers.  This enables them to negotiate with Third Party Logistics (3PL) providers for an acceptable price.  In order to check if there is any serious discrepancy between the methods used by the three they were each asked to produce estimates for the same four jobs.  The results (in hundreds of pounds) are shown in the table below:

(a)    Does the data suggest any discrepancy between the estimators?

(b)   Is it possible to identify any interaction between estimators and jobs?  Explain your answer.

(ii) Two computer operating systems were compared to test the disc access response times.  The results (in milliseconds) are shown below:

Does it seem that there is a significant difference between the two operating systems?