Explanation
The message "The amount of system memory has changed" indicates that there is a problem with the random access memory (RAM) modules in the computer. The RAM may be loose, faulty, or incompatible with the motherboard or other components. The GPU, HDD, and CPU are not directly related to system memory and would not cause this message to appear.

Explanation
Dot Matrix printers do not use heat, they use a pin striking an inked ribbon (for the first copy, the subsequent copies are handled by the carbon paper) The ribbon is low on ink or missing and must be replaced to get proper output in a dot matrix printer that uses carbon paper. References: CompTIA A+ Certification Exam Guide, Exam 220-1001, Page 361

Explanation
correct answer is "Overclocking" and "Reduce CPU Clock speed" CPU is at 4.5 Ghz when normal is 3.2 Ghz.
Overclocking too much can cause freezes, and this is a gaming computer so the user probably took it too far.
http://blog.logicalincrements.com/2018/12/4-troubleshooting-tips-overclocking-pc/

Explanation
A picture containing text, electronics, printer Description automatically generated

Explanation
The issue of video but no audio on a projector in a conference room can be resolved by utilizing an HDMI connection between the PC and the projector. HDMI supports both video and audio signals and is commonly used to connect a PC to a projector for presentations. Changing the input on the projector to VGA, changing the output on the PC to DVI, or modifying the projector's refresh rate will not resolve the issue. References:
CompTIA A+ Certification Exam: Core 1 - Objective 2.5