在爆炸性气体环境危险区域2区，固定式灯应选用( )。
A．隔爆型 B．防爆型 C．增安型 D．正压型
参考答案：A,C
下列罐头可食用的是
A．超过保存期
B．漏听
C．生物性胖听
D．物理性胖听
E．罐头内容物外观正常，酸度增加
It is he frequently returns home late makes his parents concerned about him.
A．because; that
B．that; that
C．不填; that
D．what; that
