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No. The two would never be used together.
Kinda. This is genrally used for 'digested' version of 'food', however.
Yes, they Cut it in store. They charged me for the 10” but I only needed 6”.
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