The diagram filled out if you look it up I hope that can help you
3.
I took this last year so yea
Fertile soil is valuable because there is a limited supply. Less than one eighth of land on Earth has soil that are well suited for farming.
The thick, fertile soil of the prairies took many thousands of years to develop.
The two ways that the value of soil can be reduced is help use soil correctly, peanuts were once a corp to help soil, and still can be. The soil value recycle rocks and bedrock.
The value of soil is reduced when it loses its fertility and when topsoil is lost due to erosion. Soil can be conserved through contour plowing, conservation plowing and crop rotation. The thick mass of tough roots at the surface of the soil.
Biotic Factors depend/rely on abiotic factors because living things (biotic) need nonliving things (abiotic) to survive. Biotic rely on other Biotic factors because they need the food and resources from other living things.
For example, we (biotic factors) need energy from the sun and oxygen/air ,which is abiotic factors, to live and grow. Just like plants (biotic) need the sun's energy (abiotic) to help it grow.
I hope u understand me. Sorry If u don't
Answer:
Cyanobacteria are aquatic and photosynthetic, that is, they live in the water, and can manufacture their own food. Because they are bacteria, they are quite small and usually unicellular, though they often grow in colonies large enough to see. They have the distinction of being the oldest known fossils, more than 3.5 billion years old, in fact! It may surprise you then to know that the cyanobacteria are still around; they are one of the largest and most important groups of bacteria on earth.