A modification has been made to the process for producing a certain type of film. Becaus...

A modification has been made to the process for producing a certain type of film. Because the modification involves extra cost, it will be incorporated only if sample data mean developing time by more than 1 second. Assuming that the developing-time distributions have the same shape and spread, use the rank-sum test at level .05 and the following data to test the appropriate hypotheses: