【简答题】A biome is a major biotic community characterized by the dominant forms of plant life and the prevailing climate. It is a major ecological community, extending over a large area and usually characteri...
【判断题】出口导向战略指一国通过鼓励本国具有比较优势的产品出口来发展本国产业和经济。
【单选题】The Great Plains are a broad expanse of grassland.
【简答题】相对弯曲半径 R/t 越小,则弯曲时回弹()。A. 越小 B. 越大 C. 没有影响 D. 可以忽略
【判断题】出口导向战略指一国通过鼓励本国具有比较优势的产品出口来发展本国产业和经济。
【单选题】All of the following statements are true of the northern Great Plains EXCEPT
A.
Summer temperatures are very hot, while winter temperatures are very cold
B.
An unbroken prairie now extends from the western mountains to the eastern forest
C.
The original vegetation consisted of shortgrass, mixed grass, and tallgrass
D.
A large number of small wetlands are found throughout the region
【多选题】减小弯曲件回弹的措施()。
A.
改进弯曲件的设计,避免使用过大的弯曲相对半径r/t
C.
对冷作硬化的材料须先退火,使其屈服点降低,必要时采用加热弯曲
【单选题】Plains are large areas of ______.
【单选题】相对弯曲半径 R/t 越小,则弯曲时回弹( )。
【简答题】_______ are used in plains where rainfall is less and climate is moderate. ______ are preferred wherever rainfall is more. _____ are used to cover large column free areas required for auditoriums, fac...