问题
单项选择题
Fire dampers prevent the spread of fire by（）.
A.convection
B.conduction
C.radiation
D.direct contact
答案
参考答案：A
搜题请搜索小程序“爱下问搜题”
Fire dampers prevent the spread of fire by（）.
A.convection
B.conduction
C.radiation
D.direct contact
参考答案：A