Water samples with BOD values of 4 ppm and 18 ppm, respectively are:

Which of two water sample A & B with BOD of 10ppm and 20 ppm respectively, then mark correct option

The COD values of three water samples A,B and C are 60 ppm, 990 ppm and 120 ppm respectively. The most polluted water sample is

Three samples of water A, Band C have the D.O levels of 4 ppm, and 3.8 ppm and 2.1 ppm respectively the most polluted sample of water is

Four samples of water A. B, C and D have the D.O. levels of 4 ppm. 3.8 ppm, 2.1 ppm and 4.9 ppm respectively 1he most polluted sample of water is

The BOD values of four samples of water A,B,C and D are 165 ppm. 120ppm, 20ppm and 5ppm respectively . The most polluted and least polluted water sample are

The concentration of fluoride, lead, nitrate and iron in a water sample from an underground lake was found to be 1000 ppb,40 ppb,100 ppm and 0.2 ppm, respectively. This water is unsuitable for drinking due to high concentration of