Ask unlimited questions for free
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."
A seasonal flu vaccine is the best way to reduce the chances you will get seasonal influenza and spread it to others.
In 1864, the first barbiturate (barbituric acid) was synthesized.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
Human kidneys will clean about 1 million gallons of blood in an average lifetime.
For a complete list of videos, visit our video library
