20. is Memphis Tennessee
21. is Knoxville Tennessee
Oil is one of Saudi Arabia's major exports.
Answer:
Biome.
Explanation:
Ecology can be defined as the scientific study of the relationship between living organisms such as plants and animals in relation to their physical and biological environment.
An ecosystem can be defined as the natural living habitats of both living and non-living organisms, in which they interact with one another. Essential services such as plant pollination, water purification, nutrient cycling etc that are being provided by the ecosystem are really very vital, important and useful for the sustenance of life, both for humans and enhances social welfare. It is generally considered to be stable if it's capable of applying self-regulating mechanisms in order to return to an equilibrium state, after an experiencing an outside disturbance or perturbation. Thus, a stable ecosystem maintains a natural balance of nutrients and energy.
In Ecology, a relatively distinct terrestrial region comprising of plants, micrograms and animals, and characterized by similar environmental factors such as relative humidity, temperature, wind, rainfall, etc., regardless of where it occurs in the world is called a biome.
There are five (5) main types of biomes and these are;
I. Forest.
II. Aquatic.
III. Desert.
IV. Grassland.
V. Tundra.
Answer:
Each layer in the Earth's crust changes in fundamental ways the closer it is to the planet's core. There are four layers of the Earth, and each layer has a different density, composition, and thickness. Three hundred years ago, English scientist Isaac Newton created the foundation for current scientific thought about the density of the Earth’s layers.
