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ChuahECS152A/EEC173A2 2.(30 points) Random Access. (a)(16 pt.) Compare, briefly in 1 or 2 sentences, unslotted Aloha with CSMA/CD according to the following: •(4 pt.) The kinds of channel feedback required. Unslotted Aloha: receiver will broadcast received signal. Sender waits for round-trip-delay to find out whether transmission is successful. CSMA/CD: Listen to carrier while transmitting a frame to detect collision. •(4 pt.) The retransmission methods. Unslotted Aloha: Wait a random amount of time and retransmit CSMA/CD: Wait a random amount of time and sense the channel again, if idle, send, otherwise, keep sensing the channel.•(4 pt.) Which one (give reasons) works better if the propagation delay is large? •(4 pt) Which one (give reasons) works better when the load is high? (b)(4 pt.) Describe p-persistent CSMA without collision detection (c)(5 pt.) State how changing the value of p from 1 to 0 affects throughput and delay of p-persistent CSMA without collision detection.