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 verb âmountingâ in this context means having the operating system in the guest virtual machine take control of some media (in this case a CD-ROM drive) and make it accessible as a file system. CD-ROM drives are usually mounted read-only. Attaching a file in the host operating system to the virtual CD device. Instructing the operating system running in the VM to mount the CD-ROM (which is really just the file mentioned in step 1) so that the files on it are visible to software running under the VMâs operating system.