AIEEE Questions

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The atomic mass of an element depends upon the number of protons, electrons and neutrons in the atoms which make the elements.

Administered prices are prices set by government or firms which are not determined by regular market forces. They do not vary in response to short-run fluctuations in demand and supply conditions.

Examples include price controls and rent controls.

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.

Demography is the scientific study of Birth and death, The well being and the Growth of population. In brief, it is the study of human populations based on their size, composition and distribution across space – and the process through which populations change.

Quakers are members of a group with Christian roots that began in England in the 1650s. Sir William Penn was an English nobleman, writer, early Quaker, and founder of the English North American colony the Province of Pennsylvania.