CA索引包括
A．著者索引
B．分子式索引
C．专利索引
D．关键词索引
E．累积索引
参考答案：A,B,C,D,E
The effective annual yield for an investment is 10 percent. What is the yield for this investment on a bond-equivalent basis （）
A. 10.00%.
B. 9.76%.
C. 9.96%.
射线OC是∠AOB的平分线，则∠AOC与∠AOB的关系是______．
