Most life forms cannot use N2 as it exists in the atmosphere. are able to convert N2 to reactive nitrogen, which can then be used by other life forms.

Nitrogen fixing bacteria

Explanation:

Nitrogen-fixing bacteria are the microbial organisms that play an important role in the conversion of atmospheric nitrogen gas into reactive nitrogen such as ammonia, nitrogen oxide, and nitrous oxide. These types of bacterias are comprised of an enzyme known as the 'nitrogenase enzyme' that allows the nitrogen gas to mix with hydrogen and eventually produces ammonia.

This ammonia is then concentrated in the soil and is later taken up by the plants which are highly essential for them as they ammonia are their main source of nitrogen. This helps in the growth, development, and expansion of the overall plant body.

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.