Mask /Pefo 128.171.0.0 255.25500 (n6) 255.255 255.0 /24) 255.255255.0 /24) 255.255.255.0 /24) 255.255 255.0 V24) 255.255.255.0 /24) 255.255255.0 /24) 255.255.2S5.0 U24) 255.255 255.0V24) 255.255 255.024) 255.25500 (/16) 172.40.6.0 172.30.12.0 0.0.0.0 19. In the original classful address scheme, was it possible to determine the class of an address from the address itself? Explain. 20. If an ISP assigned you a /25 address block, how many computers could you assign an address? 21. Can a host have more than one IP address? Explain. 22. Fragments from multiple datagrams can arrive out-of-order. How does it reassemble? 23. A datagram cannot be reassembled until all fragments arrive. Explain what will happen if one or more fragments from a datagram arrive and other fragments are delayed or lost? 24. How many response does a computer except to receive when it broadcasts an ARP request? Explain. 25. How does a computer know whether an arriving frame contains an IP datagram or an ARP message? 26. When does ARP algorithm create a new entry in an ARP cache? 27. What type of addresses are used in layers below ARP? 28. If a datagram has an incorrect destination IP address in header, which ICMP error message will be received