Over a four-year period, lakeisha thompson purchased shares in the oakmark i fund. using the information below, answer the questions that follow. you may want to review the concept of dollar cost averaging in chapter 12 before completing this problem. (round your answers to 1 decimal place.) years investment amount price per share number of shares february 2014 s 3,900 $ 52.00 february 2015 3,900 33.00 february 2016 3,900 $ 46.40 february 2017 3,900 $ $ 54.00 es a. at the end of four years, what is the total amount invested? total investment b. at the end of four years, what is the total number of shares purchased? (round your intermediate calculations and final answer to 1 decimal place.) total shares c. at the end of four years, what is the average cost for each share? (round your intermediate calculations to 1 decimal place and final answer to 2 decimal places.)