Last year, your firm collected data on each of its 107 division managers. The data contain growth figures for each manager's division, the manager's tenure with the firm, and the manager's score on a leadership test, which was administered firmwide. These data are contained in the file Chop7 Prob14.xIsx. Click on the link below to access the dataset. Excel Data File Instructions: Enter your responses rounded to two decimal places. a. Run a regression designed to determine the effect of manager tenure on division growth. Growth=+Tenure+Score b. What role, if any, can the manager's leadership test score play in the regression you ran for Part a? Proxy variable Control variable Confounding factor Dependent variable