How is lake Erie getting dirty?

What region are states that the Appalachian mountains pass through? Should a stockpot be covered? What is a sea? What route would a ship traveling from pacific ocean to the port of Washington? Where is the Salmon River Public in Riggins located? Where is lake Tahoe Lake Mead and lake lahaton? Which human activity has probably contributed most to the acidification of lakes in the Adirondack region? Why the Yellowstone Caldera is the most dangerous volcano? Does the raging bull go upside down? What river flows through through central Europe into the Black Sea? What are you forbidden to do in a snuff zone? What are the negative and positive effects of mass tourism? How are mineral deposits in lakes and on the ocean floor formed? What is Niagara falls gallons that fall per minute? What invention encouraged tourism in 1920? Where is the Decordova Museum And Sculpture Park in Lincoln Massachusetts located? What major river flows into the Mississippi river? Is Shah Jahan buried in the Taj Mahal? What occurrence in the middle of the Pacific Ocean affects the pink shaded areas along the coastline? Suez Canal and Hungary in 1956?