项目A的收益率为0.03,标准差为0.02,则变异系数为()。
A.1.5
B.0.67
C.0.01
D.0.0006
参考答案:B
解析:
I ____ you to buy tickets first if you want to travel in August. [ ]
A. advice
B. advise
C. ask
D. tell
齿条式千斤顶的起重能力较小,油压千斤顶的起重量可达()t。
A.50
B.500
C.5 000
D.5