Balsa wood is classified as a hard wood!
41
Columbia University has developed an artificial tree that passively soaks up carbon dioxide from the air using "leaves" that are 1,000 times more efficient than true leaves that use photosynthesis.
15
The average temperature at 40,000 feet above sea level is -60 F.
56
Your brain is 80% water.
525
One cubic foot of gold weighs more than 1,200 pounds!
78
One barrel of petroleum holds 42 gallons.
20
Scientists have developed a microparticle filled with oxygen that can be injected into the blood stream, enabling us to live without breathing.
21
Iron weighs more after it rusts.
68