root@carolyns-laptop:~# mount -o remount.rw /dev/sdb3 /media/external
mount: /dev/sdb3 already mounted or /media/external busy
mount: according to mtab, /dev/sdb3 is already mounted on /media/external
root@carolyns-laptop:~# cp -arfvp '/home/carolyn/Desktop/Windoze.iso' '/media/external' 
`/home/carolyn/Desktop/Windoze.iso' -> `/media/external/Windoze.iso'
cp: cannot create regular file `/media/external/Windoze.iso': Read-only file system