检查液化石油气钢瓶漏气的最好方法是什么？
参考答案：
用肥皂水、涂抹在欲检漏的部位。
Can you tell me ________?[ ]
A．when did it happen
B．when it happened
C．when was it happened
D．when it was happened
施工成本管理的措施中最易为人接受和采用的措施是( )。
A．组织措施B．技术措施C．合同措施D．经济措施
