1 cubic metre
1m2
I'm assuming you mean one meter deep with a one square meter footprint. The answer is 1*1*1=1m^3 = one cubic meter. Actually, that is how much dirt was taken out to make the hole. There should be no dirt in the hole, otherwise it wouldn't be a hole.
None. Its a hole
600mm into cubic meter
None. All the dirt is removed to make the hole!
None. A hole is the absence of the material.
None. If it's a hole, then the dirt has been removed.
125 cubic feet
none, its a hole.
None. It's a hole. The earth has already been removed. If you remove any more, it's a different size hole.
as deep mas the hole was when it was a whole hole.
That hole is 6 feet deep or 72 inches deep.