Answer:
12 oktober 1492 is Christopher Colombus arrive to North America
before Christopher Colombus the Native Americans, also known as American Indians, Indigenous Americans where there about 20000 years
Explanation:
The law of multiple proportion state that elements combine in small whole number ratio to form compounds. The law accounts for the stoichiometry relationship that exist among elements in a chemical compound.
The final treatment of wastewater in the united states normally involves treatment with Chlorine to make it safe.
The final stage of the wastewater treatment process, which is when it is often carried out in most treatment plants, can also include chlorination. The primary goals of this chlorine addition are water disinfection and maintaining chlorine residuals that will stay in the water as it moves through the distribution system.
In the US, wastewater treatment facilities treat over 34 billion gallons of wastewater per day. Human waste, food waste, and some soaps and detergents all contribute nitrogen and phosphorus to wastewater. Once the water has been cleansed to the standards required and observed by state and federal authorities, it is often released into a nearby water body.
learn more about the treatment of wastewater here:
brainly.com/question/14375418
#SPJ4
Europe needed to rebuild its economy after the war.
