Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
One cubic foot of gold weighs more than 1,200 pounds!
78
Pure water (H2O) does not conduct electricity on its own.
46
Cold water weighs more than hot water.
93
Aluminum used to be more valuable than gold!
84
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Hot water can freeze faster than cold water.
181
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79