Section ATroubleshoot each problem describing the most probable cause and a suitable solution:$1.$ A small business with three workstations, a file server and a network printer connected all of them to a hub but, when transferring large files, they are facing communication disconnections and file transfers must restart all the time. $2.$ Two new desktop computers with IP addresses $169\mathrm{.}254\mathrm{.}0\mathrm{.}1$ and $169\mathrm{.}254\mathrm{.}0\mathrm{.}2$ can ping each other but they dont have Internet connection. $3.$ A router allows communications between two networks A and B$.$ There is a DHCP server in the network B$.$ A client in the network A cant get a dynamic IP address from the DHCP server, but there is communication by ping if trying with static addresses. Section BRespond to the following questions:$4.$ What is the difference between CSMA$/$CD and CSMA$/$CA$?5.$ Name two devices that can contain a collision domain. $6.$ Name two devices that can contain a broadcast domain $($you may need some additional research$).7.$ What protocol have in common the tools ping and tracert? In what layer of the OSI model does it operate? $8.$ What a patch panel is used for?