The Surface Overflow Rate (SOR) in a rectangular sedimentation tank is $45 \mathrm{~m}^3 / \mathrm{m}^2 / \mathrm{d}$. Minimum diameters of spherical inorganic and organic particles expected to be completely removed in this tank are calculated. Assume that Stoke's law is applicable. Which of the following options is/are correct: Specific gravity of inorganic particles $=2.65$ Specific gravity of organic particles $=1.20$ Acceleration due to gravity $(\mathrm{g})=9.81 \mathrm{~m} / \mathrm{s}^2$ Kinematic viscosity $(v)=1 \times 10^{-6} \mathrm{~m}^2 / \mathrm{s}$

Aeration is employed as a treatment option for the removal of several pollutants from contaminated water. Identify the pollutant(s), where aeration is employed as a part of their removal:

Which of the following is/are NOT active disinfectant(s) in water treatment?