Ask unlimited questions for free
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
Illicit drug use costs the United States approximately $181 billion every year.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.
For a complete list of videos, visit our video library