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Did you know?

There can actually be a 25-hour time difference between certain locations in the world. The International Date Line passes between the islands of Samoa and American Samoa. It is not a straight line, but "zig-zags" around various island chains. Therefore, Samoa and nearby islands have one date, while American Samoa and nearby islands are one day behind. Daylight saving time is used in some islands, but not in others—further shifting the hours out of sync with natural time.

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Sildenafil (Viagra®) has two actions that may be of consequence in patients with heart disease. It can lower the blood pressure, and it can interact with nitrates. It should never be used in patients who are taking nitrates.

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Asthma cases in Americans are about 75% higher today than they were in 1980.

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Amoebae are the simplest type of protozoans, and are characterized by a feeding and dividing trophozoite stage that moves by temporary extensions called pseudopodia or false feet.

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On average, the stomach produces 2 L of hydrochloric acid per day.

The Tsavo Man-Eaters on display in the Field Museum of Natural History in Chicago, Illinois. The Tsavo Man-Eaters on display in the Field Museum of Natural History in Chicago, Illinois.
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This 1900 photograph of steel factories at night in Duquesne, near Pittsburgh, was tinted by hand. S This 1900 photograph of steel factories at night in Duquesne, near Pittsburgh, was tinted by hand. S
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Display of Canapés Display of Canapés
A very light ideal spring stretches by when it is used to hang a 135-N object. What is the ... A very light ideal spring stretches by when it is used to hang a 135-N object. What is the ...
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