Hi,
>>"Is there a way to identify the objects on the layers that I want to delete?"
see Patchys answer, he used command LAYDEL to see if a layer is used inside a block,
for a test it is okay and a good help (don't save, undo this step).
Just the hint to use laydel if you can't purge a layer isn't a really good hint (in my eyes),
LAYMRG to 0 is the way to go.
But laydel and laymrg is just good to find layers in blocks,
newer software products can use PURGE command to find much more,
for example Attributes which refer to a layer.
Purge, switch to the second view (unpurgeable objects), select the item you want to purge and
read the information listed below.
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Your sample file:
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