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Author Question: The U.S. population growth rate in the first half of the 19th century was a. about the same as that ... (Read 61 times) |
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.
Children of people with alcoholism are more inclined to drink alcohol or use hard drugs. In fact, they are 400 times more likely to use hard drugs than those who do not have a family history of alcohol addiction.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.