单项选择题
A network interface port has collision detection and carrier sensing enabled on a shared twisted pair network. From this statement, what is known about the network interface port?（）
A.This is a 10 Mb/s switch port. B.This is a 100 Mb/s switch port. C.This is an Ethernet port operating at half duplex. D.This is an Ethernet port operating at full duplex. E.This is a port on a network interface card in a PC
单项选择题 Whichspreadspectrumtechnologydoesthe802.11bstandarddefineforoperation?（）
多项选择题 Whataretwosecurityappliancesthatcanbeinstalledinanetwork?(Choosetwo.)（）
多项选择题 Whataretworecommendedwaysofprotectingnetworkdeviceconfigurationfilesfromoutsidenetworksecuritythreats?(Choosetwo.)（）
