Earth���s inner core is solid because of
a. the composition of its rock.
b. its great diameter.
c. extreme cold.
d. immense pressure.

within these regions are all the major types of biomes in the world. a biome is a community of animals and plants spreading over an extensive area with a relatively uniform climate. some diverse biomes represented in north america include desert, grassland, tundra, and coral reefs.

river is shown in this type of map