If water is so abundant on earth, why are water resources such a big concern?

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

According to the sector model, in which region or regions would you most likely find industrial and transportation development?

What is the best evidence for the plate tectonics?