HIV crossed from chimps to humans in the 1920's in what is now the Democratic Republic of Congo. This was probably as a result of chimps carrying the Simian Immunodeficiency Virus (SIV), a virus closely related to HIV, being hunted and eaten by people living in the area.
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Of the more than 7,000 chemicals in tobacco smoke, at least 250 are known to be harmful, including hydrogen cyanide, carbon monoxide, and ammonia (1, 2, 5). Among the 250 known harmful chemicals in tobacco smoke, at least 69 can cause cancer. These cancer-causing chemicals include the following (1, 2, 5)
Explanation:
The answer is letter C.
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Most common cases of poisoning occur at
home while others through occupational and environmental exposures. Its
symptoms vary depending on the type of poison, length of exposure, quantity of
poison, and the age of a person involved. If someone is experiencing symptoms
of poisoning (e.g. dizziness, vomiting, trouble breathing) it is always best to
contact a Poison Control Center immediately. These people know and have a great
dealing with different hazards and could suggest possible first aids for the poisoning.</span>
