等离子弧切割工件搁架应离地()mm,并应安装局部除尘装置
A.300
B.400
C.500
参考答案:B
--- The windows are broken and need to be repaired.
--- I think so. They can hardly _____ the cold now.
A.keep out
B.give out
C.take out
D.put out
下图为陆地环境主要构成要素的相互关联图。读图,完成1—2题。
1、松花江和珠江水文特征不同,关键是图中哪个箭头所起的作用?[ ]
A.①
B.②
C.③
D.④
2、能表示黄土高原地貌特征形成的箭头是[ ]
A.⑤
B.⑥
C.⑦
D.⑧