One barrel of petroleum holds 42 gallons.
20
Out of all the senses, smell is most closely linked to memory.
146
During photosynthesis, plants emit light humans can’t see, but NASA can see that light from space - and they've even made maps of it!
21
The average temperature at 40,000 feet above sea level is -60 F.
56
Scientists in Germany have developed a candy that doesn't cause cavities.
11
Scientists have revived a flowering plant from a fruit stored away in permafrost by Arctic ground squirrel 32,000 years ago.
16
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Iron weighs more after it rusts.
68