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Author Question: A 330 10 resistor and a 470 5 resistor are connected in parallel. Taking into account the ... (Read 41 times) |
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Certain chemicals, after ingestion, can be converted by the body into cyanide. Most of these chemicals have been removed from the market, but some old nail polish remover, solvents, and plastics manufacturing solutions can contain these substances.
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.