In the earth's mantle, heat is transferred in large convection currents. within these currents,
a.
hotter and cooler rock sink but do not rise.
b.
cooler and hotter rock rise but do not sink.
c.
hotter rock rises and cooler rock sinks.
d.
cooler rock rises and hotter rock sinks.

Which ecosystem best fits the characteristics listed below? which ecosystem best fits the characteristics listed below? ii. seasonal migrations of millions of wildebeests, zebras, and elephants iii. large numbers of predators, such as lions iv. acacia trees and grasses a. the congo rainforest b. the african mangroves c. the serengeti grasslands d. the sahel