单向通道保护环的触发条件是（）告警 ["TU－AIS","AU－AIS","LOS","RDI"]
Refer to the exhibit. Look at the command output. Assume that there is no other path，and the configuration is correct. What would be the consequences of this situation？（） ["Users in SW1 can ping SW2 but not vice versa.","Users in SW2 can ping SW1 but not vice versa.","Users in SW1 and SW2 can ping each other.","Users in SW1 and SW2 cannot ping each other."]
医患关系
Which three capabilities make the Cisco Nexus 7010 switch an effective solution for the data center core？ （） [" virtualization"," unified I\/O"," support for 48-port Gb\/s line card"," support for Data Center Service Modules"," high performance"," high availability"]
在工程项目的经济评价中，如果参加评选的方案所产生的效益无法或很难用货币来计量，这时进行方案比选可以采用（）。 ["差额内部收益率法","净现值率法","增量分析法","最小费用法"]
结合史实简要说明明清时期农业发展所呈现的特点，并分析由此而对社会经济所产生的影响。
