单项选择题
A.Send ACK 1-3
B.Send ACK 3
C.Send ACK 4
D.Send ACK 4-6
E.Send ACK 6
F.Send ACK 7
多项选择题 Host1正在试图和Host2联系。RouterC的e0接口是down的，以下选项正确的是？（）
单项选择题 How many subnets can be gained by subnetting 172.17.32.0/23 into a /27 mask, and how many usable host addresses will there be per subnet?（）
单项选择题 As a network administrator，you have been instructed to prevent all traffic or iginating on the LAN from entering the R2 router.Which the following command would implement the access list on the interface of theR2 router？（）
