Explanation
The technician's next step after testing the theory and determining the theory is confirmed is to establish a plan of action to resolve the problem and identify potential effects. This step involves preparing a specific method to implement the solution and considering how the solution might affect other components or users. The technician should also test the plan in an isolated environment before applying it to the actual system.
Implementing the solution is not the next step after testing the theory and determining the theory is confirmed, as it requires establishing a plan of action first. Documenting lessons learned is not the next step after testing the theory and determining the theory is confirmed, as it comes after verifying full system functionality and implementing preventive measures. Verifying full system functionality is not the next step after testing the theory and determining the theory is confirmed, as it comes after implementing the solution.

Explanation
A Knowledge Base is a collection of information that provides solutions to common problems or issues encountered by IT professionals. A Knowledge Base can be accessed online or offline, and can be maintained by an organization or a vendor. A help desk technician should check the Knowledge Base first before trying other methods, as it may contain the answer or a workaround for the issue3. References := CompTIA IT Fundamentals (ITF+) Study Guide, 2nd Edition, Chapter 6: Security2

Explanation
Memory is the component of a computer system that stores data temporarily for fast access by the processor.
Memory does not need to remain persistent, which means it does not retain data when the power is turned off.
A programmer can use memory to store output in a place that can be accessed as quickly as possible by the processor. Memory is also known as RAM (random access memory). References : The Official CompTIA IT Fundamentals (ITF+) Study Guide (FC0-U61), page 36.

The best solution for the technician to resolve the issue quickly is to add an access point for the users. An access point is a device that provides wireless connectivity to the network. An access point can be connected to a wired network and extend its coverage to wireless devices, such as laptops, smartphones, or tablets. By adding an access point on the west side of the building, the technician can enable the users' laptops to connect to the internet wirelessly without changing their hardware or software settings. Adding a switch and hardwiring the users' laptops is not a quick solution, as it would require installing cables and configuring the network settings on each laptop. Adding a network router is not necessary, as a router is a device that connects multiple networks and routes traffic between them. A router does not provide wireless connectivity by itself, unless it has a built-in access point. Replacing the users' laptops with desktop computers is not a feasible solution, as it would incur high costs and inconvenience for the users. References: CompTIA IT Fundamentals (ITF+) Study Guide: Exam FC0-U61, Second Edition, Chapter 3: Infrastructure, pages 90-91