Which of these is a benefit of using fossil fuels?
o
a. they contribute to global warming
o
b. they are very convenient to use
c. they add pollutants to the air
o
d. they are available in a finite amount.

Benefit of using fossil fuels  is "They are available in a finite amount"

Explanation

Fossil fuels are the energy generated from the living things. They are easily accessible and are available abundantly. It provides large quantity of concentrated energy and are low cost and easily available. It includes coal, natural gas, petroleum. Fossil fuels have high calorific value. They are cheaper and non conventional form of energy. It is easy to locate the place where it is available abundantly. 1 gram of fossil releases huge amount of energy.  

Competition. interaction among organisms that compete for the same natural resource (food, shelter, water, space) in an ecosystem. predation. an interaction in which one organism kills another for food. predator. prey. symbiosis. mutualisum. commensalisum. parasitisum.

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