Examples of abiotic factors are water, air, soil, sunlight, and minerals.Biotic factors are living or once-living organisms in the ecosystem.
Biotic describes a living component of an ecosystem; for example organisms, such as plants and animals.
Examples Water, light, wind, soil, humidity, minerals, gases.
<u><em>Hope this helps!</em></u>
Hello there ^ _ ^
I believe the answer is : A - Evolution
Good luck!
The reason why nost scientists thought that the first true cells formed on Earth were anaerobic is being shown in the second option :B. because there was no oxygen on early Earth. Paying attention to this fact scientists discovered that first cells were prokaryotes and greatest part of them created oxygen as a toxic by-product of their own metabolism which make them understand how the planet was provided with oxygen and made a conclusion that first cells were anaerobic.
By process of elimination you can find the right answer. We know for a fact that carbon is found in all living organisms. That is why we talk about carbon based life forms. So the first statement cannot be true. You can figure out how many Valence electrons an element has by looking at the group number. The group number of carbon is 4 so the 2nd statement cannot be true. We know that carbon does bond with other elements because it is not a noble gas and therefore must be able to form compounds.
This means the answer must be they can form up to four covalent bonds
