March was a wake-up call for the market. But not only because stock and bond prices fell. It was a reminder to ETF investors in particular that you’d better know what you own. So in the spirit of Passover, the Jewish holiday that starts this week, and the traditional Seder meal that commemorates freedom from slavery during biblical times, I am supplying four questions I think are critical for ETF holders to ask themselves. For those unfamiliar with Passover, the four questions are a basic discussion of wh ...