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Author Question: In a contest, two tractors pull two identical blocks of stone the same distance over identical ... (Read 1609 times) |
It is difficult to obtain enough calcium without consuming milk or other dairy foods.
Though the United States has largely rejected the metric system, it is used for currency, as in 100 pennies = 1 dollar. Previously, the British currency system was used, with measurements such as 12 pence to the shilling, and 20 shillings to the pound.
The tallest man ever known was Robert Wadlow, an American, who reached the height of 8 feet 11 inches. He died at age 26 years from an infection caused by the immense weight of his body (491 pounds) and the stress on his leg bones and muscles.
Every 10 seconds, a person in the United States goes to the emergency room complaining of head pain. About 1.2 million visits are for acute migraine attacks.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.