11. What makes up the lithosphere!
a. continental crust
b. crust and upper mantle
c. oceanic crust
d. upper mantle

12. How would you compare the densities of the Earth's crust, mantle, and core?
a. The mantle is less dense than the core but denser than the crust.
b. The mantle is less dense than both the core and the crust.
c. The mantle is denser than the core but less dense than the crust.
d. The mantle is denser than both the core and the crust.

13. What is the most abundant abundant element in the Earth's crust?
a. hydrogen
b. calcium
c. oxygen
d. nitrogen

14. The Earth's crust is made up of what types of rock/metal?
a. liquid iron and nickel
b. silicate rocks and iron
c. solid iron and nickel
d. granite and basalt

15. These metals/rocks make up the mantle.
a. liquid iron and nickel
b. silicate rocks and iron
c. solid iron and nickel
d. granite and basalt

16. The inner core is made up of
a. liquid iron and nickel
b. silicate rocks and iron
c. solid iron and nickel
d. granite and basalt

17. If the Atlantic Ocean is widening at a rate of 3 cm per year, how far (in km) will it spread in a million
years?
a. 3 km
b. 30 km
c. 300 km
d. 3000 km

18. Which of the following increases with distance from the mid-ocean ridge/
a. age of oceanic lithosphere b. thickness of lithosphere
c. depth of seafloor
d. all of these

19. Why does the oceanic crust sink beneath the continental crust at the subduction zone?
a. The oceanic crust has a greater density.
b. The oceanic crust is pulled downward by Earth's magnetic field.
c. The oceanic crust is pushed from the ridge.
d. The continental crust has a denser composition.

20. Which among the following is caused by movement of the crust and upper mantle?
a. puzzle-like fit of continents b. magnetic evidence in rocks c. rock formation d. coal deposits​