Answer:
For Marla,
Number of shares purchased is 100 @ $8 per share
Initial Position = 100 * 8 = $800
Dividends Received = $200
Brokerage Paid = 75 + 75 = $150
Current Value of Stock = $7
Current Position for 100 shares @ $7 per share
Current Position = $700
Holding Period Return = Profit/Initial Investment
Holding Period Return = ((700 - 800) - 150 + 200)/800
Holding Period Return = -6.25%