Evidence suggests that originally the Earth's atmosphere contained a large amount of carbon dioxide and almost no oxygen. Our atmosphere is different today: it contains a large amount of oxygen, which is good, since we need it to breathe. What caused this atmospheric change? A) Global warming B) A meteor impact C) Photosynthetic organisms like cyanobacteria taking in carbon dioxide and releasing oxygen. D) Photosynthetic organisms like cyanobacteria taking in oxygen and releasing carbon dioxide.

Which process collects sample soils from particular areas of a site? a.) repetitive sampling b.) restorative sampling c.) random sampling d.) representative sampling

What type of coastline is commonly found along the western side of the america’s

Directions you probably already know that people have different ways to organize their ideas. some people make lists or outlines, some draw pictures, while others may combine these two methods. experiment with different note-taking techniques to find the one which works best for you. one common note-taking technique is webbing. webbing uses the sizes of circles to indicate the importance of items. lines are used to indicate the relationships between items. the example below is based on the information presented in a previous lesson. notice that the circle for "geography is" appears at the center of the web. it has larger than the circles that surround it. the "geography " circle is surrounded by smaller circles of earth's atmosphere, earth's climate, earth's surface. notice the lines that connect these items to the concept of geography. notice that the circles surrounding atmosphere are smaller. also observe that the lines that connect the items and indicate the relationships between the items. webbing will you capture the most important points in your lessons. beginning with lesson two, geographic tools: globes and maps, use webbing to take notes on the important information in this unit. hint: it will be easier to complete this project if you take your notes after completing each lesson.