show using Excel please

4. Suppose you borrowed 10,000 Blackstone Inc. (BX) shares from your broker and sold them for $64.81 per share at the end of 2020. Your broker requires 50% initial margin in short sales, which you covered using the T-bills in your account. BX paid a dividend of $3.57 per share during 2021. a. What was your profit if you covered your short position at the end of 2021, when BX was trading at $129.39 per share? b. If your broker had a 40% maintenance margin requirement, how far could BX rise to before you received a margin call? C. How much money would you have to put into your account in order to satisfy the maintenance margin requirement if BX suddenly increased to $80 per share