Marsupials are pest put some are not but some of them are mammals and some of them are not. I guessed it should be either way .
It refers to the cost or benefit of an activity by an economic agent for which it does not pay a price.
Fr ex: factory produces goods , it releases harmful smokes n polluts our enviroment.
In this case externality implies the negetive effect.
Hope it helped u!!
A
Planting the same crop over and over again depletes the nutrients of the soil and it also allows any pests to get used to the soil. That’s why many people practice crop rotation.
Answer:
c
Explanation:
The very primitive and early microorganisms on the earth's surface were protobionts. Protobionts are cell-like microscopic structures, and they are made up of organic and inorganic molecules present in a lipid bilayer membrane. The layers of the lipid membranes were folded into bilayers and transformed into a bubble shape when placed in water. These membranes were selectively permeable and also observed shrinkage and swelling in osmotic conditions. Protobionts also possess the characteristics of reproduction.
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