About how long have wastewater treatment plants been in existence?

Suppose you had to resolve the problems believed to be caused by distance decay in russia. what would you suggest?

The middle east links which two continents? ●asia and europe●europ and africa●africa and asia●africa and australia

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