20. During periods of economic expansion, the spread between corporate bonds and U.S. Treasuries generally: a. widens. b. narrows. c. stays the same. d. becomes negative. 21. The yield curve is normally plotted using Treasury securities because: a. they have a wide range of maturities. b. it is easier to obtain accurate and complete dati on them. c. they have no default risk. d. it is easier to obtain historical data on them. 22. Relative to their holdings in their early careers, conservative retirees likely have greater holdings of: a. small-cap stocks. b. intermational stocks. c. cyclical stocks. d. low-beta stocks