Author Question: The two most common elements found in Earth's crust are: a. silicon and magnesium. b. sodium and ... (Read 63 times)

sam.t96 · **on:** Aug 7, 2018

The two most common elements found in Earth's crust are:
a. silicon and magnesium.
b. sodium and carbon.
c. silicon and aluminum.
d. silicon and oxygen.
e. sodium and potassium.

Question 2

The Mohorovicic discontinuity:
a. marks the boundary between Earth's crust and mantle.
b. has been reached by drilling in the Gulf of Mexico.
c. separates Earth's inner core from the outer core.
d. indicates a change in rock type from basalt to granite.
e. indicates a change in rock type from igneous to sedimentary.