The very ubiquity of electronic communications can have a surprising downside , notes Richard Kohn, a military historian at the University of North Carolina: a wife becomes accustomed to frequent e-mail from her husband, until he can’’t get to a computer. And then her anxiety increases.

A．failure

B．underside

C．drawback

D．consequence

压力式温控制器用（）

A.温包感温，将温度信号转变为电阻信号

B.温包感温，将温度信号转变为压力信号

C.热敏电阻感温，将温度信号转变为电阻信号

D.热敏电阻感温；将温度信号转变为压力信号