a. How many shares can Lauren purchase using the maximum allowable margin? Round your answer down to the nearest whole share, if necessary. shares b. What is Lauren's profit (loss) if the price of Gentry's stock i. rises to $40 ? Use a minus sign to enter loss, if any. Round your answer to the nearest dollar. Use the rounded value of the number of shares from part a. $ ii. falls to $20 ? Use a minus sign to enter loss, if any. Round your answer to the nearest dollar. Use the rounded value of the number of shares from part a. $ $