How many of the world’s 20 largest cities are located in western europe?
a. none
b. one
c. two
d. four

These factors threaten north americas ecosystems

The vegetation that thrives in the tundra is limited to a. mosses, barley, wheat, and corn. b. coniferous trees. c. dwarf shrubs, mosses, lichen, potatoes, and beans. d. mosses, lichen, algae, and dwarf shrubs.

Which types of seismic waves travel through earths interior? select all that apply. a) l waves b) p waves c) s waves