Each workstation in the final assembly area of a large manufacturing facility has a “backlog” area to hold units that are to be processed. A production engineer believes there could be a relationship between the number of units in the backlog area and the productivity of the worker. Specifically, the engineer thinks increasing the number of units in the backlog area might lead to workers being more in a hurry to “catch up,” hence increasing their productivity. The data in file XR17061 show the results of a test in which the engineer tried various backlog levels and measured productivity at 50 different workstations. Generate a scatter diagram relating y = productivity (units/hour) to x = number of units in the backlog area, then apply an appropriate polynomial model to fit the data. Does there appear to be any relationship between the variables? How much of the variation in productivity is explained by the model?