镁粉是制造烟花的重要原料之一。生产镁粉时，将镁蒸气在某种气体中冷却。下列可作为冷却气体的是[ ]
A．空气
B．氮气
C．氩气
D．二氧化碳
答案：C
单词拼写。
1.It's r_________ to even think about going out in this storm.
2.He a_________ an escape from prison, but couldn't find anybody to help him.
3.No words can c________ my thanks to you at the moment.
4.A l_________ is a person who is in charge of or works in a library.
5.I am a_________ to taking a walk after supper.
6.The government has set up a working party to look into the problem of drug a______.
7.This is an article written by a leading sports j________.
8.His parents have a________ of his going abroad with friends this summer.
9.I s_______ an apple and drank the juice.
10.An a________ arrived in five minutes after the accident.
按照FIDIC《施工合同条件》规定，因非承包商原因导致不能进行规定的竣工检验，工程师应以( )签发接收证书。
A．本该进行检验日B．缺陷通知期内补充检验通过日C．工程实际移交日D．业主实际使用日
