<u>Answer:
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When the outer electron shell is full in an element, this creates a Noble gas.
<u>Explanation</u>:
Noble gases are the elements that belong to group 18 in the periodic table. Noble gases are also called as inert gases. The outermost shell of the noble gases are fully filled by electrons. Due to this the noble gases don’t react with any other elements and remain isolated.
There are 6 noble gases in the periodic table. They are helium (He), Argon (Ar), Neon (Ne) Krypton (Kr), Radon (Rn) and Xenon (Xe). Noble gases conduct electricity. They are fluorescent, odorless and colorless. Noble gases are used a maintain stable elements in a constant and safe environment.
Answer:
Cold fronts form when a cooler air mass moves into an area of warmer air in the wake of a developing extratropical cyclone. The warmer air interacts with the cooler air mass along the boundary, and usually produces precipitation
Hemoglobin is contained in red blood cells,which efficiently carries oxygen from the lungs to the tissues of the body. It also helps in the transportation of carbon dioxide and hydrogen ions back to the lungs.
Answer:
E. Population - community - ecosystem - biosphere
Explanation:
Population is the set of organisms of the same species
Community is where organisms of different species live and communicate together
ecosystem is a biological system where ocommunities and environment are present.
Biosphere is where all ecosystem are present. (let´s say, the earth)
