Question

Which layer of the Earth shown on the diagram is the hottest?
A crust
B mantle
C inner core
D outer core
How are the Earth's inner and outer cores similar?
A They are both solid.
B They are both liquid.
C They are both made of nickel and iron.
D They are both made of basalt and igneous rocks.

Answer 1

1) C — inner core. It's the hottest layer; temperature increases with depth toward Earth's center.

2) C — they are both made of nickel and iron. (They differ in state: the inner core is solid, the outer core is liquid.)