Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65
At 15 years old, Jack Andraka invented a method of diagnosing pancreatic cancer, thus helping to save the lives of millions of people around the world. It is 168 times faster, 26,000 times cheaper, 400 times more sensitive, and has a 99% success rate.
15
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Iron weighs more after it rusts.
68
Forensic scientists can determine a person's sex, age, and race by examining a single strand of hair.
101
A ball of glass will bounce higher than a ball made of rubber.
73
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
One cubic foot of gold weighs more than 1,200 pounds!
78