One cubic mile of seawater contains about 50 pounds of gold.
79
The Caspian Sea is also classed as the world's largest lake.
52
It takes a drop of ocean water more than 1,000 years to circulate around the world.
61
The Atlantic Ocean is saltier than the Pacific Ocean.
54
The water of the Antarctica is so cold that nothing can rot there.
334
Every year, Alaska has about 5,000 earthquakes.
31
10 of the tributaries flowing into the Amazon river are as big as the Mississippi river.
41