Understanding Basic IP Routing 105 Answers 1. Correct answer and explanation: D. You add 128 + 64 for the first two ones to get 192. Incorrect answers and explanations: A, B, and C. Answer A is incorrect, 128 would be 01111111. Answer B is incorrect, 191 would be 10111111. Answer C is incorrect, 137 would be 100010011. 2. Correct answer and explanation: D. Addresses that begin with 224 are used for multicasting. Incorrect answers and explanations: A, B, and C. Answer A is incorrect, this is for network management. Answer B is incorrect, this is for browsing the web. Answer C is incorrect, this is for receiving e-mail. 3. Correct answer and explanation: B. The system has failed to get an IP address from a DHCP server and has assigned itself an automatic private IP address, which only allows for local communication. Incorrect answers and explanations: A, C, and D. Answer A is incorrect, the system would not have been assigned a static IP address in this range. Answer C is incorrect, this is a valid private APIPA address. Answer D is incorrect, classless addressing is not a factor in this problem.