So some rocks are radioactive because they have radioisotopes in their nuclei. Also they may have radon gas trapped in their crystals if they are igneous rock. They could also be radioactive due to the fact that the atom of the rock is unstable.
Connecting USB Devices Manually. Choose VM > Removable Devices to connect specific USB devices to your virtual machine. You can connect up to two USB devices at a time. If the physical USB devices are connected to the host computer through a hub, the virtual machine sees only the USB devices, not the hub.
USB002 is also a Virtual Printer Port that appears if USB001 is already in use with another USB printer. The port works the same as USB001 in allowing you to select it for your USB printer and completing the installation process. Windows' Devices and Printers Add a Printer utility also walks you through your printer's installation process after selecting USB002.