How many elements make up 98% of the earths crust

The process by which liquid water changes into water vapour is called what?

What was one effect of European influence on Southeast Asia?

World War One was primarily about, while World War Two largely concerned a) land/oil b) nuclear arms/mining rights c) oil/human rights d) nationalism/race or ethnicity

Greeks propose the world is composed of what

What is fusion? How does it work in stars?

What Is one way a rift can form

Pioneers farmers settling the grasslands of the American West often built houses of sod, while early settlers of the eastern forest built wooden structures like log cabins. This suggests that building materials:

Troposphere is heated from below because the atmospheric gases are not good absorbers of what kind of radiation

Which nations produce more of the world's pollution? OLDCS OMDCS

How are the agricultural economies of Chile and Peru similar and different?