please make this questions understandable for to review.

The maximum initial margin as established by the Federal Reserve is 50 percent. The maintenance margin is 25 percent. Suppose that you have $25,000 in cash that you are able to invest in stock XYZ which currently sells for $20 per share. The stock pays no dividends.

a) If you buy on margin, what is the maximum number of shares that you can purchase? (2)

b) Ignoring interest expenses, if you buy the maximum number of stocks in part a) now, at what stock price will you get a margin call from your broker? (3)

c) Suppose that the share price falls to the value computed in part b) and you decide to send additional cash to meet the margin requirement. What is the minimum amount of additional cash you need to send to your broker? (4)

d) If the stock price actually goes up from $20 per share to $45 per share over a year. For your margin account, interest costs are 8 percent annually. What is the percentage return over the year on your initial $25,000 investment in this case? (3)