Hi Guys,

Can anybody help me for the following 3 questions?


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1. Network IDs defined only by two bytes of an IP address are called:


A: Class A networks
B: Class B networks
C: Class C networks
D: Class D networks
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Which OSI layers can be mapped to the TCP/IP 'Application Layer'?


A: Session and Presentation layers
B: Network and Transport layers
C: Transport and Application layers
D: Session, Presentation and Application layers
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In the OSI model, which layer manages sessions between endpoints?


A: Presentation Layer
B: Network Layer
C: Transport Layer
D: Session Layer
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Totally how many OSI layers, by the way??

Thanks in advance
Cheers,
Bhaskar Kommuru