将全部投资资金集中投资于短期证券或长期证券的投资方法属于( )投资法。
A．期限分离
B．分散化
C．灵活调整
D．债券交换
参考答案：A
使脉压增大的情况是
A．射血期延长
B．外周阻力增大
C．心率加快
D．体循环平均压降低
E．大动脉的可扩张性减少
— I'm sure Andrew will win the first prize in the final.
— I think so. He ______ for it for months. [ ]
A. is preparing
B. was preparing
C. has been preparing
D. had been preparing
