The principle that states the undisturbed rock sequence has the oldest rocks on the bottom is known as
a. relative age dating.
b. original juxtaposition.
c. superposition.
d. original parallelism.

countries such as spain, france and portugal colonized the region. although most of latin america was colonized by spain, the countries of portugal and france also had major influences on the region. due to war and disease, native populations were decimated.

two jet streams that directly affect the formation of weather in the continental part are a polar jet and a subtropical jet. they are responsible for the transportation of weather systems, which directly affect people. the polar front is the boundary between cold air from the north pole and warmer equatorial air. both the polar jet and the subtropical jet blow from the west to the east, and follow the boundary between cold and warm air.

the strongest jet streams are polar jets, while subtropical jets are somewhat weaker.

the right answer is c. the polar jet stream is generaly stronger than the subtropical jet stream.