Answer:
Deep ocean currents.
Explanation:
In cold regions, such as the North Atlantic Ocean, ocean water loses heat to the atmosphere and becomes cold and dense. When ocean water freezes, forming sea ice, salt is left behind causing surrounding seawater to become saltier and denser. Dense-cold-salty water sinks to the ocean bottom.
I would need a picture to help you
4. The Roman Empire
( Muslim Empire is not a thing)
Sustainable use practices are practices that are used in the use of resources for example that seek to maintain the longevity and continuance of the potential use of that resource. In regards to trees and logging the sustainable use of wood or paper would seek to continue the longevity and vitality of the forests by not overusing these products. Sustainable use will use a resource at a rate that will allow for natural replenishment or incremental use of the resource to prevent harm to the environment and allow the resource to be used far into the future.
