How much of the Earth's atmosphere do scientists believe was made of oxygen 2.3 billion years ago?

A.) 70%

B.) 22%

C.) 1%

D.) 10%

Describe the two kinds of weathering and the three kinds of erosion that shape the surface of the earth

When lava cools so quickly that the minerals do not have time to organize in their crystal lattice, What is the texture

Salinization is a common agricultural problem in what type of region?

Which region has a higher level of economic development? Eastern Europe Western Europe

Using your understanding of global wind systems and the general circulation of Earth's atmosphere, what is the name of the global wind or pressure system that is most likely responsible?

Cartographers can make a projection all the way around the Earth by approximating a (n) blank - which is like wrapping a piece of paper around the globe and casting shadows onto it. O A. fingerprint O B. mushroom O C. rolling print D.

you can greatly your risk of a collision by learning how to navigate the highway transportation system and by using safe skills. answer option reduce, increase, balance, develop

How was the Great Leap Forward supposed to increase China's production? A. by replacing private ownership of farms with common ownership B. by combining China's collectives into self-sufficient People's Communes C.

Oil and natural gas result from

A sphere made of steel is put in water and, surprisingly, it floats. Develop a hypothesis to explain this observation.