The coral reef community is best described as a community based on animals that migrate from one area of ocean to another. true or false?

Scientists think that convection currents flow in earth’s a. continents. b. mantle. c. lithosphere. d. inner core.

Given: circle a externally tangent to circle b. how many possible common tangents to circles a and b can exist? 2 3 4

17. the soil erosion pictured here is the result of what? a. harvesting renewable resources at a rate greater than the sustainable yield b. a mudslide caused by excessive rains c. harvesting renewable resources at a rate lower than the sustainable yield d. the transition between geologic eras and eons