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Did you know?

When blood is deoxygenated and flowing back to the heart through the veins, it is dark reddish-blue in color. Blood in the arteries that is oxygenated and flowing out to the body is bright red. Whereas arterial blood comes out in spurts, venous blood flows.

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As many as 20% of Americans have been infected by the fungus known as Histoplasmosis. While most people are asymptomatic or only have slight symptoms, infection can progress to a rapid and potentially fatal superinfection.

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Blood is approximately twice as thick as water because of the cells and other components found in it.

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Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.

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Russia has the highest death rate from cardiovascular disease followed by the Ukraine, Romania, Hungary, and Poland.

By reflecting most visible light, snow creates a much cooler microclimate than nearby bare ground. By reflecting most visible light, snow creates a much cooler microclimate than nearby bare ground.
Two Scottish reindeer relax after pulling Santa's sleigh at the switching on of Christmas light Two Scottish reindeer relax after pulling Santa's sleigh at the switching on of Christmas light
Air flows through the PCV valve during idle, cruising, and light-load conditions. Air flows through the PCV valve during idle, cruising, and light-load conditions.
When both sides of the back have been massaged, redrape the back. With light to moderate force, use ... When both sides of the back have been massaged, redrape the back. With light to moderate force, use ...
Light energy from the Sun powers Light energy from the Sun powers
Forces Acting on Plates Forces Acting on Plates
Video: Global warming and its effect on climate change

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