A baseball pitcher's earned run average (ERA) is A(e,i) = 9e / i, where e is the number of earned runs given up by the pitcher and i is the number of innings pitched. Good pitchers have low ERAs. Assume that e 2 0 and i > 0 are real numbers. 3. During his best season, a certain pitcher pitched a total of 172 innings and gave upjust 27 earned runs. What was his ERA? b. Determine the ERA of a relief pitcher who gives up 4 earned runs in one-third of an inning. c. Graph the level curve A(e,i) =2, and describe the relationship between e and i in this case