Northern Ireland is the smallest of the four countries of the United Kingdom in terms of both area and population, containing 2.9% of the total population and 5.7% of the total area of the United Kingdom.
If you are using a wireless mouse with a USB connector and a PS/2 keyboard, verify that the USB mouse is plugged in a USB port on the computer and that the purple keyboard PS/2 plug is connected to the purple PS/2 port on the computer.
The USB port is a long, flat rectangle with a tab the plug fits into. A USB plug will only fit into a USB port one way, and it will easily slide in. If the mouse doesn't work with either of the USB ports on the keyboard, try each port on the computer. If you have another mouse, plug it in. If that mouse works and your old one doesn't, your old mouse needed to be replaced.