Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Cold water weighs more than hot water.
93
Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
The hair of an adult man or woman can stretch 25 percent of its length without breaking.
116
Every day, plants convert sunlight into energy equivalent to six times the entire power consumption of human civilization.
9
For every gallon of sea water, you get more than a quarter pound of salt.
45