Answer:
Microbes, salts, and pollution from agriculture and industry all contribute to the problem. Global warming will likely have major impacts on the world's freshwater resources.
Explanation:
Water source protection involves the protection of surface water sources and the protection of groundwater sources from contamination of any kind. Water source protection includes basic measures and rules such as the installation of a fence around the source or the banning of grazing animals in the surrounding area.
This is because elements are pure substances with only one atom. When two or more elements are combined, you get compound elements; which allows for more substances to be created.
Answer: Valves in the veins
Explanation: The flow of the blood inside the body takes place through the veins and arteries. The oxygenated blood from the heart is supplied to the different parts of the body.
The blood flows from the capillaries to the venules and from there to the veins. The blood moves in the veins by the rhythmic movement of the smooth muscles in the body.
Most of the blood moves against the gravity so there is a chance that it can backflow so to prevent this there are valves in the veins known as one way valves.
The native is the best way
