Solar wind particles can be captured by the Earth's magnetosphere. When these particles spiral down along the magnetic field into the atmosphere, they are responsible for: a. the reddish color we see during sunsets b. tropical storms (regions of rapidly rotating air) c. aurorae (northern and southern lights) d. the poor quality of television programming in the world's northern hemisphere e. the greenhouse effect

Distance that the transcontinental railroad covered from omaha to san francisco.

Which of the following best describes the circumstance under which countries block the importation of certain products into their country? a. importation blockade b.trade barrier c.trade inhibitor d. domestic protection act

Ageologist is working in an area with exposed sedimentary rocks and finds a well exposed sequence of stratified rocks. as he works through a thick sequence of limestone, he sees abundant large clam fossils that produce an interlocking texture suggesting a reef, but within the limestone section these clams disappear and the overlying limestone is made up primarily of fragments of corals. he now moves 50 km away and finds limestones interbedded with shales, and the limestones contain the same clam fossils he had seen previously 50 km away. as he continues through this section, the rocks become entirely limestone, and the clams disappear again with coral fossils above forming a reef structure. he concludes