Imagine that scientists have discovered a new planet that is apparently devoid of life but has ice caps located at the poles. these ice caps reveal that the planet's atmospheric o2 levels sharply increased about 1,000,000 years ago but then quickly dropped 50,000 years ago. what could account for these changes in atmospheric o2 levels?

Alaina wants to decide whether her current cell phone plan is better than a package that another company offers. to compare the two plans, she plotted two lines on a graph, where y represented the total cost of one month’s service and x represented the megabytes of data that she used in a month. which part of the graph will represent the cost per megabyte of data used in each plan?

1. in 1492, spain expelled after being under their rule for centuries. a. the portuguese b. the basques c. the castilians d. the moors 2. an important cultural center during the renaissance was the city of a. milan b. bologna c. florence d. naples 3. what is the connection between the minoan civilization and a volcanic eruption on thera? a. the earthquake happened a century before the collapse of the civilization. b. the earthquake created a graben. c. the earthquake caused the collapse of the civilization. d. the earthquake caused a volcanic eruption. 4. throughout history, other cultures influenced greece through a. military conquest b. shared ideals c. trade agreements 5. geographically, spain is isolated from the rest of europe by a. portugal b. the atlantic ocean c. the pyrenees mountains d. narrow coastal plains 6. most of central spain is known as the meseta, which is the spanish word for a. mountains b. plateau c. peninsula d. plains 7. for the people of ancient greece, the  iliad, and the  odyssey  a. copied western ideals b. were not popular c. presented community standards d. were children’s poems\ 8. western cultures got many of their ideas about from ancient greece. a. warfare b. democracy c. education d. agriculture 9. how is greece’s natural vegetation similar to that of other mediterranean countries? a. it has been damaged by forest fires. b. it is mainly deciduous forests. c. it grows rapidly in the wet climate. d. it has been reduced to scrub vegetation by overgrazing. 10. what is the most productive agricultural area in italy? a. the alps b. the po valley c. southern italy d. the apennines 11. many factories in northern italy use for energy. a. coal b. hydroelectricity c. nuclear energy d. natural gas 12. what major landform covers much of italy? a. the apennines b. the po river valley c. the alps

Based on what you know about the location of the earth in relation to the sun, why is this called the goldilocks zone in other galaxies? a. it's a region that exhibits a weak gravitational pull, thus maintaining a safe distance from the sun. b. it's an area that doesn't experience any major weather events that could cause mass extinctions. c. it's an area that's an optimal distance from the sun for potentially supporting life. d. it's a region that's unaffected by asteroid or meteor impacts.