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.
5. Make the flash drive bootable. Use the bootsect utility that is shipped with Windows 7/Vista. To do so: 1  Insert the Windows 7/Vista DVD and note down the drive letter of the DVD drive. 2  For this guide, the DVD drive is D: and the USB drive is G:. 3  Navigate to the directory where bootsect is found.