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

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. The water is unsuitable for drinking due to high concentration of-