5.下列计算正确的是( )
| A. | 9a3•2a2=18a5 | B. | 2x5•3x4=5x9 | C. | 3x3•4x3=12x3 | D. | 3y3•5y3=15y9 |
3.在下列调查中,适宜采用普查方式的是( )
| A. | 了解市民对马来西亚沉船事件的关注度 | |
| B. | 了解初三(1)班学生期末立定跳远成绩 | |
| C. | 为监测嘉陵江重庆段的物种生态情况 | |
| D. | 为掌握全国人民对王源联合国演讲的看法 |
2.在实数-$\frac{5}{3}$、$\frac{{\sqrt{2}}}{4}$、0.125、$\sqrt{\frac{25}{16}}$、-$\frac{π}{2}$中,分数的个数是( )
0 293459 293467 293473 293477 293483 293485 293489 293495 293497 293503 293509 293513 293515 293519 293525 293527 293533 293537 293539 293543 293545 293549 293551 293553 293554 293555 293557 293558 293559 293561 293563 293567 293569 293573 293575 293579 293585 293587 293593 293597 293599 293603 293609 293615 293617 293623 293627 293629 293635 293639 293645 293653 366461
| A. | 0 | B. | 1 | C. | 2 | D. | 3 |