The boy _______ in the teachers’ office was found _______ at the school gate yesterday.

A．standing, smoking

B．standing, to smoke

C．stood, smoking

D．stood, to smoke

某车间设有局部排风系统，局部排风量为0.56kg/s，冬季室内工作区温度为15℃，冬季通风室外计算温度为-15℃，采暖室外计算温度为-25℃(大气压为标准大气压)，空气定压比热1.01kJ(kg·℃)。围护结构耗热量为8.8kW，室内维持负压，机械进风量为排风量的90%，试求机械通风量和送风温度为下列何项

A．0.3～0.53kg/s，29～32℃
B．0.54～0.65kg/s，29～32℃
C．0.54～0.65kg/s，33～36.5℃
D．0.3～0.53kg/s，36.6～38.5℃