(a) Refer to Exercise 12-1. Based on historical information, the company believes that the type of industry that the customer belongs to influences web development time. Suppose that there are four industry types: manufacturing, banking, airlines, and health care. Discuss model formulation in this context and define the variables.

(b) What is the possible utility of thismodel relative to that formulated inExercise 12-1?

(c) Explain what the coefficient of the variable associated with the banking industry means.

(d) Can you comment on the value of R2a for the model here versus that formulated in Exercise 12-1? What about comments on R2?