Which statement best describes energy of an ecosystem?
the amount of energy entering an ecosystem from the sun is equal to the amount lost as heat.
the amount of energy entering an ecosystem from the sun is equal to the amount used by organisms.
the amount of energy entering an ecosystem from the sun is equal to the amount used by organisms plus the amount lost as heat.
the amount of energy entering an ecosystem from the sun does not transfer from organism to organism.

The amount of energy entering an ecosystem from the Sun is equal to the amount used by organisms plus the amount lost as heat.  

Explanation:

An ecosystem is a basically a community in which several living organisms live together in a certain area and share food and other living resources.

When we talk about prime source of energy for any ecosystem it is considered to be the, Sun. Sun is the source of energy for all living organisms and the energy of sunlight is primarily used by green plants to prepare food through the process of photosynthesis. In this process sunlight is fixed into energy compounds like ATP. And once the green plants are eaten by other higher animals like goat, some of the energy is wasted as heat and other is transferred into the body of next organism. Then when the goat is eaten by higher animal like lion, some of the energy is wasted as heat and other is transferred into the body of next organism. This process goes on.

In this way, the energy from sun is transferred from herbivores like goat to carnivores like lion etc. Some energy is used by the higher organisms while the other is lost as heat during energy transfer process.

Therefore, mentioned option, "The amount of energy entering an ecosystem from the Sun is equal to the amount used by organisms plus the amount lost as heat" is correct option.

the correct answer, according to e2020, is the second choice there is an occluded front in region a and a cold front in region b.