In what may be our last quiz, ever, Tom turns the tables and puts Don in the hot seat with a Wall Street Journal high-school personal finance quiz—covering the Magnificent Seven, Roth IRAs, TIPS, efficient markets, yield curves, market risk, and dollar-cost averaging. Don does reasonably well, but not without protesting a dubious “debt avalanche” question and getting tangled up in a couple of accounting and risk terms. After the quiz-show nonsense, the guys tackle a listener question from Jos...