Treatment at these plants is quick, taking only about seven hours to remove most of the pollutants from the wastewater. In the natural environment this process could take many weeks and nature alone cannot handle the volume of wastewater that New York City produces.
By Dr Ananya Mandal, MD. Life expectancy refers to the number of years a person is expected to live based on the statistical average. Life expectancy varies by geographical area and by era. In the Bronze age, for example, life expectancy was 26 years, while in 2010, it was 67 years.In mathematical terms, life expectancy refers to the expected number of years remaining for an individual at any given age.ife expectancy varies by geographical area and by era. In the Bronze age, for example, life expectancy was 26 years, while in 2010, it was 67 years. In mathematical terms, life expectancy refers to the expected number of years remaining for an individual at any given age.
The word  longevity  is sometimes used as a synonym for  life expectancy  in demography-however, the term longevity is sometimes meant to refer only to especially long lived members of a population, whereas life expectancy is always defined statistically as the average number of years remaining at a given age.he word  longevity  is sometimes used as a synonym for  life expectancy  in demography-however, the term longevity is sometimes meant to refer only to especially long lived members of a population, whereas life expectancy is always defined statistically as the average number of years remaining at a given age.