Investing in your mutual fund bydollar-cost averaging can smooth outthe market's peaks and valleys. Thedownside comes when you sell.Unless you unload all the shares,you're going to be faced with a mazeof share lots, each with a differentcost basis. Fidelity (800-343-3548;www.fidelity.com) is one companythat will come to your rescue, calculatingprofit or loss and allowing youto choose specific share lots to sell. Ifyou own other mutual funds andyou're mathematically challenged,however, it may be easiest to use theaverage-cost basis that the fund companygives you. If you're brave, however,you can slog through the mathto pinpoint the lots you want tosell. To cut down on capital gainstaxes, it's usually best to sell theshares with the highest cost basis.