" Drained sewage has B.O.D."

Drained sewage has BDO

Drained sewage has biological oxygen demand (BOD) :

Drained sewage has biological oxygen demand (BOD) :

What is B.O.D.:-

What is B.O.D.:-

Expand B.O.D.

Expand B.O.D.

Which of the following is not true about sewage(i) Sewage is more in rural areas(ii) Sewage water is useful for crop plants (iii) Nitrates are one of the impurities of sewage(iv) Draining out sewage water is good method for cleaning the area