用括号内所给词的适当形式填空。

1. The post office isn't far. You can get there                (easy).

2. Tom enjoys                 (skate) very much.

3. The                  (five) month of a year is May.

4. Bill got up                  (early) than his sister.

5. Three American                  (visit) came to our school yesterday.

在投资项目可行性研究阶段进行敏感性分析时，所使用的经济分析指标之一是 ( )。

A．净现值率
B．借款偿还期
C．投资回收期
D．投资收益率