Why are components that are naturally found in air be considered air pollutants?

It is because components of air like carbon dioxide can be considered as a pollutant when the concentration of these gases is larger than the normal range due to human activity like the burning of fossil fuel. At a higher concentration, even the naturally occurring gases may have an undesirable effect on the environment. The high level of carbon dioxide can cause an increase in the earth's temperature.

1. (1.2kw)x(15/60hours) = .3kwh --> a

2. (5kw)x(90/60hours)x(8cents/kwh) = $0.60 --> d

3. microwave --> 1200 watts = (1.2kw)x(6/60hours) = .12kwh

coffee-maker --> 900 watts = (.9kw)x(10/60hours) = .15kwh

therefore, it requires more energy for the coffee-maker to do the same amount of work.

so the answer is a.

your answer should be c) enjoy!