this is Wireless Network, please answer number 5,6,8,9,10

Grade: Part 1: Objective-Multiple Choices. Please choose the best answer. There is neandonly one 1. 802.11 wireless networking uses what method as the a. CSMA/CD b. TDMA c. CSMA/CA d. CDMA best answer. (20 pts) 2. a. b. c. d. 802.11b specifies data rates of what? 6, 18, 24, 36, 48 and 54 Mbps 1,2, 5 and 11 Mbps 150 and 300 Mbps 1 and 2 Mbps 3. 802.11 physical layer techniques. 3.1 What physical layer technique does 802.11b wireless use? a. DSss b. FDMA c. UMTS d. OFDM 3.2 What physical layer technique does 802.11a wireless use? a. DSss b. FDMA UMTS d. OFDM 4. Which of the following IEEE wireless LAN standards uses only the band of frequencies (around 5.4GHz 5.8GHz)? a. 802.11a b. 802.11b c. 802.11g 5. Which of the following answers is the correct maximum speed and physical technique at which two IEEE WLAN devices can send data with a particular standard? a. 802.11b, using OFDM, at 54 Mbps b. 802.11g, using OFDM, at 54 Mbps c. 802.11a, using DSSS, at 54 Mbps d. 802.I1a, using DSSS, at 11 Mbps