Industrial cities are mostly surrounded by grre cover forests while producing goods release a lot of CO∨2 and CO...sice forests are also known as carbon sinks(i.e,they absorb lots of CO∨2 n balance the level of O∨2 and CO∨2 in the atmosphere)therefore to balance the % of oxygen and carbon dioxide in air , green cover forests are found to surround the industrial cities....hope i helped u:)

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