Tom decided to buy 10 ABC stocks, whose closing price on the previous day was $20 per share. He placed a limit order at $19.95, which was not executed. The market closed on that day at $20.10. The following day, the order was revised to $20.15 per share, and 8 stocks were filled at that price. The market closed at $20.18. Within the components of implementation shortfall, the missed trade opportunity costs are ______. a. 0.18% b. 0.3% c. 0.4% d. 0.2%