监控系统是以一个变电所的一次设备作为其监控对象的。
参考答案：错
Nine in ten parents said there were significant differences in their approach to educating their children compared with __ of their parents.
A．those
B．one
C．both
D．that
企业与企业之间的电子商务（B2B）具体功能有哪些？
