Which of the following is a result of natural erosion?
a. desert sands
b. lost seed germination
c. widened valleys
d. all of the above

Which of teh following would explain the importance of the trans-siberian railroad to russia's economy? (schoology test)

What statement about the economy of france is not true? a. paris is a major manufacturing center b. marseille is a busy seaport on the mediterranean coast c. farming is the major activity in the alps. d. world-famous wines are produced in the bordeaux region c. farming is the major activity in the alps

What id the primary human cause of the global warming a. storage of nuclear fuel rods b. burning of fossil fuels c. building of high-density housing d. violent conflicts over natural resources