在三维空间画多线段用()命令。
A.多线段PLINE
B.三维多线段3DPOLY
C.PLINE或3DPOLY
D.LINE
参考答案:B
将秸秆粉碎,碎料压块,再将压块填进供热锅炉中,这是齐齐哈尔市引进加拿大技术经改制而成的冬季供热新招,目前这项新技术正在东北三省运行。回答1-2题:
1.若各地开始供暖的室外气温大致相同,则下列图中四城市供暖期最长的是[ ]
2.用秸秆代替燃煤而产生的生态效益主要表现在[ ]
A.降低供热成本
B.减轻空气污染
C.促进农民增收
D.调整能源结构
So _____ that all the living things died out gradually .
A.serious polluted the lake is
B.serious polluted is the lake
C.seriously polluted the lake is
D.seriously polluted is the lake