What three factors determine if something is pollutant?

They include: Chemical nature of the pollutant - how active and toxic it is to humans, plants and animals; Concentration - the amount of the chemical per unit volume of air, water, soil, and; Persistence or longevity - how long the pollutant remains in the environment in its harmful form.

Explanation:

Air pollutants like ozone, particulate matter, carbon monoxide, nitrogen oxide, sulfur dioxide, lead cause atmospheric pollution which regards to ozone depletion, GH effect, climate change and human health effects. If anyone say the main factors of air pollution beyond of industry, means of transportation, solid waste generation and urbanization.

Growing urbanization and industrialization grows more pollution. Due to a large number of population in the world, more pollution is generated. Specifically if we talk about air pollution, due to steady increase in number of industries, the gradient level is deteriorating day by day. There is no good if we just talk about sustainable development if we are not following it.

Explanation:

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current