管道温度传感器的触发温度是（华氏）（）
A.190°F
B.250°F
C.360°F
D.490°F
参考答案：A
主动债券组合管理中的骑乘收益率曲线方法通常适用于中长期投资。（）
—Mr. Smith always has _______ to tell us. [ ]
A. some good pieces of news
B. some pieces of good news
C. some good piece of news
D. some piece of good news
