我国规定光监控通路的工作波长为（）。 A.1650nm B.510nm C.980n

长期借款与其他长期负债筹资相比，其特点为( )。

A．筹资速度较慢
B．借款弹性较大
C．借款成本较高
D．限制条款较少

单词拼写。

1. Greatly _____( 鼓舞) by the teacher's words91 have made up my mind not to give up my goal.

2. Small shops were _____( 挤满) out by supermarkets  during the economic crisis.

3. Trees can provide _____ ( 树荫)from the sun, so they can reduce cooling costs in summer.

4. In general, I was quite pleased with his ____. (behave)

5. I hold the firm belief that you are bound to achieve your dream of being admitted to a key university,

    which will give you a wonderful sense of  ____ . (achieve)

继承机制的作用是

A．信息隐藏

B．数据封装

C．定义新类

D．数据抽象

结晶器内溢钢的原因有哪些？