A limited wireless range after replacing the wireless card could indicate that the antenna is not properly connected to the card, or that the antenna is damaged or obstructed. According to the web search results, some possible steps to troubleshoot and verify the antenna's connection are:
Open the laptop case and locate the wireless card and the antenna wires. Make sure that the wires are securely attached to the card's connectors, and that they are not loose or broken12.
Check the position and orientation of the antenna. Make sure that it is not blocked by any metal objects, walls, or other sources of interference. Adjust the angle or location of the antenna if possible to improve the signal strength3.
Replace the antenna with a new one or a compatible one from another device. Test the wireless range and performance with the new antenna2.

The frequency bands that 802.11b and 802.11g operate in are 2.4GHz bands, which allow for longer range but lower speed than higher frequency bands such as 5GHz or 6GHz bands used by newer standards such as
802.11a/n/ac/ax.

To fix a Cat 5 cable issue where the cable fails when it is moved around, the technician would need to use an RJ45 connector (option E) and a crimper (option F). The technician can use the crimper to attach a new RJ45 connector to the end of the cable, which should resolve the issue.
An RJ45 connector (option E) is a type of connector commonly used for Ethernet networking. It is an
8-position, 8-contact (8P8C) modular plug and jack that is used to terminate Cat 5 and other types of twisted pair cables. A crimper (option F) is a tool used to attach connectors to the ends of cables. In this case, the technician would use the crimper to attach a new RJ45 connector to the end of the Cat 5 cable.
When a cable fails when it is moved around, it often indicates that there is a problem with the connector at the end of the cable. By attaching a new RJ45 connector using a crimper, the technician can ensure that the cable has a secure and reliable connection.

Thermal paste is a substance that fills in any gaps between a CPU and its heat sink, which is a device that dissipates heat from the CPU. Without adequate thermal paste, the CPU may overheat and cause the system to shut down automatically to prevent damage. This is especially likely when running 4K video or games, which are more demanding and generate more heat. The technician should check if the CPU heat sink was attached properly and apply enough thermal paste to ensure good contact and heat transfer. Reference:
https://partners.comptia.org/docs/default-source/resources/a-core-series-combined-content-guide (page 28)

Liquid cooling is a method of cooling the CPU by circulating a liquid through a closed loop that absorbs heat from the CPU and transfers it to a radiator. Liquid cooling is more effective and quieter than air cooling, which uses a fan and a heat sink. However, liquid cooling is also more expensive and complex to install. Upgrading the thermal paste, using a copper heat sink, or upgrading the CPU fan are ways to improve air cooling, but they will not lower the CPU temperature as much as liquid cooling. References:
https://www.comptia.org/certifications/a#examdetails https://www.comptia.org/blog/what-is-liquid-cooling