Questions

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.

A mountain is what has roots that nobody sees, Is taller than trees, Up, up it goes, Yet it never grows.

In biology, Homology is defined as any characteristic of biological organisms that is derived from a common ancestor. 

Hence, Homology is evidence of Common ancestry.

IC's (Integrated Circuits) also called as Chips or Microchips whose invention allowed computers to be smaller and smaller.

Other than being the politician of India, Sushma Swaraj is Advocate by profession. She was the first women chief minister of Delhi for a brief period, Second women Minister for External Affairs after Indira Gandhi.

The law of conservation of mass states that in any closed system the mass of the system is neither created nor destroyed over time i.e, the mass cannot be changed overtime.

Hence, the given statement is true.