No, nothing changes. It is calling everything I have in this file "not selectable", including he Landsat image files I loaded, the composite from those image files and the subset from the composite are all "not selectable". If I select the composite, still nothing changes:
Oh! Yes, a couple of assignments ago the Prof said to turn on Spatial Analyst!! Didn't think that still applied. Turned it on and: Wa La! Great! Thank you, thank you!
you seem to be listing the non-selectable layer? does anything change when you select something else.