Charles,
The question-mark indicates that the computer is unable to locate a valid system folder.
Try the
PRAM reset mentioned by Kevin first. See also
KB article HT1781 about the Power Manager.
A disk image for a bootable floppy (the Network Access Disk 7.5
here) is available for download from Apple. However, you will need another semi-old Macintosh computer equipped with a floppy drive (and
Disk Copy 4.2) in order to create the disk. If absolutely necessary, a PC can be used via a special technique.
Jan