how do u burn (copy) a disc to a disc

Depends. Why not tell all about it?

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A CD to another CD with only 1 optical disc reader/burner?

Use Disk Utility (in the Finder go to the menu Go > Utilities and the open the Disk Utility App) to make a disk image of the master CD, then use Disk Utility to burn that disk image to a another disc.

This assumes you have an optical disc drive, and the original optical disc is not copy protected.

MtD

Earlier to you process,You'll have to instal CD Writer Nero(avail yearly subscription from source)/at disk level of administration.

Never the less,select the graphics and text images from recorded first CD and then use copy filter onto choose and click the second CD,Thereby paste the contents you want too.You find the files to be burnt written on,strike the burn task,few minutes the required files will be saved in second from first CD.This process is burst mode of data transfer.

Why are you suggesting software which is only compatible with Windows (and the instructions)? Most of us are Mac OS users.