please answer all

Cats and C 15. Which of the following is not a color pair in C) Blue D) Brown A) Orange B) Yellow 16. What is the purpose of the braided metal shield on coaxial cable? C) Prevent interference D) Make field terminations easier A) Increase bandwidth B) Make the cable as stiff as possible available? 17. On wireless networks in the USA, typically how many channels are C) 13 D) Depends on the configuration A) 5 B) 2.4 18. Omni-directional antennas produce what kind of 3-D signal shape? A) Donut C) Water Drop D) Round Sphere B) Ice Cream Cone 19. Which of these devices creates a Layer 2 connection between LAN clients? A) Hub B) Router C) Switch D) Firewall 20. What is the purpose of a patch panel? A) Cable storage for unused Cat5e patch cables B) Provide an endpoint for connectivity to C) Provide high speed switching capability networking cables / connections D) Ensure the maximum possible attenuation on network runs 21. The wireless standard 802.11g runs off of which main frequency? A) 5 Ghz B) 2.4 Ghz C) 5.4 Ghz D) 4.2 Ghz 22. What is the property below that fiber optic cables have that Cat5e and Coax don't? A) Easy terminations B) Immunity to electromagnetic interference D) Metallic based conductors C) Low expense