To determine if Dave could have sold fewer than 5,000 shares and met the margin call on Thursday, we need to calculate the minimum number of shares he would need to sell in order to bring his equity back to 50% of the value of his KNIGHT position.

Dave’s equity at the end of the day on Thursday is $28,000. The value of his KNIGHT position is $52,000 (8,000 shares x $7.00 per share). To calculate the minimum number of shares he would need to sell, we can use the formula:

Minimum number of shares = (Equity - 50% of KNIGHT position value) / KNIGHT share price

Minimum number of shares = ($28,000 - 0.5 x $52,000) / $7.00 Minimum number of shares = ($28,000 - $26,000) / $7.00 Minimum number of shares = $2,000 / $7.00 Minimum number of shares = 285.71

Since shares cannot be sold in fractions, Dave would need to sell at least 286 shares to meet the margin call. Therefore, he could not have sold fewer than 5,000 shares to meet the margin call.

To calculate Dave’s total return as of the end of the day on Thursday, we need to consider the initial investment, any additional purchases, sales, and the remaining equity.

Dave’s initial investment was $150,000 for 15,000 shares of KNIGHT at $10.00 per share. He made additional purchases of 7,000 shares at $12.50 per share and 15,000 shares at $10.00 per share. He sold 9,000 shares at $9.00 per share and 5,000 shares at $6.50 per share.

Total investment = $150,000 + $87,500 + $150,000 = $387,500 Total sales proceeds = $81,000 + $32,500 = $113,500

Total return = (Total sales proceeds - Total investment) / Total investment Total return = ($113,500 - $387,500) / $387,500 Total return = -$274,000 / $387,500 Total return = -0.7078 or -70.78%

Therefore, Dave’s total return as of the end of the day on Thursday is -70.78%.