空调系统按()分类,可分为全空气系统、全水系统、空气一水系统和冷剂系统。
A.所处理空气的来源
B.送风量是否变化
C.承担室内负荷的输送介质
D.空气处理设备的设置情况
参考答案:C
—The earthquake last night was really terrifying.
— , no people were injured or killed, and they escaped in time.
A.Luckily
B.Hopefully
C.Sadly
D.Unfortunately
判断下列各项那些是遗迹,那些是遗物?