To calculate Dave’s equity if the price of KNIGHT had increased to $15.00, we need to determine the value of his remaining shares in KNIGHT and add it to his cash balance.

Remaining shares in KNIGHT = 13,000 - 9,000 = 4,000 shares Value of remaining shares = 4,000 shares * $15.00 = $60,000

Equity = Cash + Value of remaining shares Equity = -$56,500 + $60,000 Equity = $3,500

Dave’s equity would be $3,500 if the price of KNIGHT had increased to $15.00.

Dave had an alternative to selling 9,000 shares at $9.00. He could have used additional cash to meet the margin call and maintain his position. However, based on the given information, it is not clear if Dave had any additional cash available.

To calculate Dave’s total return as of the end of day on Wednesday, we need to consider the cash flows from his transactions and the change in value of his remaining shares.

Total return = Cash inflows - Cash outflows + Change in value of remaining shares

Cash inflows: - Cash inflow from selling 9,000 shares at $9.00 = $81,000

Cash outflows: - Cash outflow from purchasing 15,000 shares at $10.00 = -$150,000 - Cash outflow from purchasing 7,000 shares at $12.50 = -$87,500

Change in value of remaining shares: - Change in value of remaining shares = (Value of remaining shares at the end of Wednesday - Value of remaining shares at the end of Tuesday) - Value of remaining shares at the end of Wednesday = 4,000 shares * $9.00 = $36,000 - Value of remaining shares at the end of Tuesday = 4,000 shares * $13.00 = $52,000 - Change in value of remaining shares = $36,000 - $52,000 = -$16,000

Total return = $81,000 - $150,000 - $87,500 - $16,000 Total return = -$172,500

Dave’s total return as of the end of day on Wednesday is -$172,500.