I need help with C). The answer is NOT $21690.

Bob Orleans invested $10,000 and borrowed $10,000 to purchase shares in Verizon Communications. At the time of his investment, Verizon was selling for $10 a share. a. If Bob paid a commission of $50, how many shares could he buy if he used only his own money and did not use margin? Number of shares 995 b. If Bob paid a commission of $100, how many shares could he buy if he used his $10,000 and borrowed $10,000 on margin to buy Verizon stock? Number of shares 1,990 c. Assume Bob did use margin to buy his Verizon stock. Also, assume he paid another $100 to sell his stock and sold the stock for $21 a share. How much profit did he make on his Verizon stock investment? Profit