Almost half of earth's land is made up of?
a. interior plains
b. plateaus
c. mountains
d. coastal plains

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

1. crust 1 the metallic layer at the earth's center 2. inner core 3 the firm layer between the crust and the asthenosphere 3. lower mantle 2 the layer surrounding the inner core 4. asthenosphere 4 the semi-solid layer between the top layer and the upper mantle 5. upper mantle 5 the layer between the asthenosphere and lower mantle 6. top layer 6 the earth's outermost layer 7. outer core 7 the hottest part of the mantle

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