A.255.0.0.0 B.255.255.0.0 C.255.255.255.0 D.255.255.255.255
A.50Ω,75Ω,95Ω B.50Ω,93Ω,95Ω C.50Ω,75Ω,93Ω D.75Ω,93Ω,95Ω
A.物理層 B.數(shù)據(jù)鏈路層 C.網(wǎng)絡(luò)層 D.應用層