Rural America gained greatly increased access to electricity during the thanks to the Rural Electrification Act.

Sorry but there isnt a map i would love to but if u can paste the picture of the map in my comment and i will you 

Answer is b)eutrophication occurs when excess nutrients are present in aquatic ecosystems, resulting in the increased production of plant life and the subsequent decrease in the oxygen levels of the watereutrophication occurs when there are excess nutrients in a body of water. this results in plants having more food and reproducing  more, sometimes leading to more aquatic animal life as well. ultimately, this can reduce the oxygen level in the ecosystem. 

Principle of superposition says the oldest rocks are on the bottom. therefore the relative age of the bottom layer is older.