The answer is D, all of the above.
If a planet exists near a distant star, the star may have a very slight back and forth motion.
the answer is c. hydrogen bonding
One
substance, other than the secretions from nerve cells, that is used in cell
communication are hormones.
<span>
To
add, <span>a hormone is any member of a class of signaling
molecules produced by glands in multicellular organisms that are transported by
the circulatory system to target distant organs to regulate physiology and
behaviour.</span></span>
No doubt, the United States is a powerful country in the world today. It has made its mark in the history by building a strong economy that every other nation envies, and idolizes as well. But, all that glitters is not gold. And every country has its pluses and minuses. There are some serious social issues in the United States as well that need to be dealt with to maintain the position of power and prestige, and set a true example of ideal society in the world.
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