A- Gravity. I believe it is gravity since that is the only one that makes sense in this situation. I hope i helped! :)
A vaccine works by training the immune system to recognize and combat pathogens, either viruses or bacteria.
Answer: Depending on the species they mightreproduce asexualy or they will adapt to have offspring.
Explanation:
Abiotic are the non-living physical and chemical factors that can affect the ecosystem, such as amount of water, temperature, amount of sunlight, etc.
Biotic are the living organisms inside the ecosystem, and can include humans, animals, and plants.
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