Exams

India is the 2nd largest importer of weapons in the world, as per 'Trends in International Arms Transfers 2018.

The minimum age for getting a learner's license as per the government rules is 16 years.

Sewage treatment generally involves three stages, called primary, secondary and tertiary treatment.

Primary treatment consists of temporarily holding the sewage in a quiescent basin where heavy solids can settle to the bottom while oil, grease and lighter solids float to the surface. This removes material that will either float or readily settle out by gravity. It includes the physical processes of screening, comminution, grit removal, and sedimentation.

Secondary treatment removes the soluble organic matter that escapes primary treatment. It also removes more of the suspended solids. Removal is usually accomplished by biological processes in which microbes consume the organic impurities as food, converting them into carbon dioxide, water, and energy for their own growth and reproduction.

Tertiary treatment includes removal of nutrients such as phosphorus and nitrogen and practically all suspended and organic matter from waste water.

3, 5, 8 have similar designs (four leaves placed close to a small circle and forming a symmetrical design at the centre of the figure).
2, 6, 9 have similar designs (three of the corners of the main figure are shaded black and there is a pattern formed around a ‘+’ sign at the centre of the figure).
1, 4, 7 have similar designs (there are four small circles at(the corners of the main figure and there is a wheel shaped element at the centre of the figure).