I believe you're talking about a population.
Nitrogen-fixing bacteria change nitrogen into a form of soluble nitrates that plants can use ...the air is 80% nitrogen but it is in N2 form which plants cannot use
<span>Red blood cells normally have a biconcave shape (picture a donut, but instead of a hole through the centre there's just a downward slope to the centre of the cell). If the cell takes on water, it will increase in size and the sloped areas will start to flatten out. If the cell loses water, it will begin to shrivel. Use these observations and your understanding of osmosis to answer the question!</span>
Answer: D) North Korea
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Explanation:
The United States, the United Kingdom, and France are all countries that have capitalistic economies. This means that (for the most part) private industry and the market determines what products are produced and who gets those products. I said "for the most part" because these countries don't follow a purely capitalistic structure. There are some elements of government regulation to ensure that no breakdowns occur. The regulations are also to ensure some level of fairness as well, in addition to preventing things like fraud.
On the other hand, countries like North Korea are known as command economies because the government determines what products are to be made and they determine who gets the products. This means that they set the prices as well to whatever they feel is correct (even if the market may disagree otherwise). The term "communism" is often strongly connected to the term "command economy".