淫羊藿主要含（）
A.蒽醌类成分
B.黄酮类成分
C.生物碱类成分
D.鞣质
E.香豆素类成分
参考答案：B
根据管道涂色的一般规定要求，压缩空气管道应涂（）色。
A.浅蓝
B.深蓝
C.黄
D.灰
Which of the following is a limitation of the cash flow yield measure The cash flow yield measure:（）
A. uses a 360-day year.
B. assumes that the projected cash flows are reinvested at the cash flow yield.
C. assumes a flat yield curve.
