👉🏼  Biological Oxygen Demand 5 - ( BOD 5 ).

**https://app.box.com/s/l9egjbpnhbi6gous0d7o6nv9fukpkffb**

https://app.box.com/s/l9egjbpnhbi6gous0d7o6nv9fukpkffb

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