What have you tried so far to eject the disc? There are several things you can try. IS there a disc icon on the desktop that you try and drag to where the trash is which turns into an eject icon? Do you try this and nothing happens, or maybe the disk icon dos not even show on the desktop. If that is the case you can try and eject the disk by trying the following:
Force quit the finder by clicking on the apple icon (top left corner of the screen) > Force Quit > choose "Finder" in the list > click the force quit button. Then try and eject again.
If that does not work you can restart your mac but hold down your mouse clicker (trackpad click), hold it down the entore time the mac is restarting until the mac is back at the sign in screen or desktop area.
If that does not work you can open disk utility (in applications/utilities). Inside disk utility see if the superdrive or disc shows up on the left hand side menu. If it does, select it and then at the top of the disk utility window choose the "edit" word and then "eject".
Let me know what happens.
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