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No. The two would never be used together.
No
Kinda. This is genrally used for 'digested' version of 'food', however.
Yes
?
Yes, they Cut it in store. They charged me for the 10” but I only needed 6”.
Yes
Mine is used for below ground surface water irrigation. About 1 to two feet down. But mine is driven over by vehicles as well.
A 4" shower drain fits snug on the smaller side