慢性支气管炎早期肺功能改变为（）
A.闭合气量减少
B.肺活量减少
C.残气量增加
D.一秒钟用力呼气量减少
E.肺总量增加
参考答案：D
-There is a mobile phone on the desk. Is it Li Yong's?
-It __________ Li Yong's. He went to Shanghai two days ago.[ ]
A. can be
B. can't be
C. must be
D. might be
室内空气中TVOC测定，在程序升温时，应以5℃/min的升温速率，升至（）℃。
A.200
B.225
C.250
D.300
