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.
Create your own ISO. Use these steps to make an ISO copy of your Windows DVD or USB flash drive: 1  While your Mac is started from OS X, insert the Windows installation DVD in an external optical USB drive or connect your Windows USB drive to a USB port on your Mac.hen creating an ISO image or copying drivers to a USB flash drive, make sure the device you're using works as a removable drive. Some devices mount as a fixed storage device and can't be ejected. Connect your flash drive or SD Card, then try to eject it from the Finder.