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.
The virtual machine hardware must be. compatible with Workstation 8 and later virtual machines. n Support for USB 2.0 and 3.0 requires that you configure virtual machine settings to enable USB 2.0 and. 3.0 support and that you have compatible guest operating systems and virtual machine hardware.