These are 360k disk images.  You need Teledisk to recreate the disks.
Teledisk can be found at:

    ftp://tvdog.shacknet.nu/tandy1000/system/teled212.zip

The disks should be labelled:

Msdos1.td0        MS-DOS/GW-Basic 3.20
Msdos2.td0        MS-DOS - Supplemental Programs
Utilitys.td0      Utilities 01.02.00

These are the original disks for the 3000.
