I believe its new ocean ridges and seafloor
Answer:
People are concerned because humans are pretty dependant on fossil fuels! Did you know 70% of Chinas electricity is Generated from Coal? Thats how dependant we are on Fossil fuels in just one short example,however Fossil fuels aren't bad they are great energy sources! :D Hope that helped ~Feel Free to mark brainliest~
Answer:
(A) It connects Western and Central Europe.
(C) It is an important trade route.
(D) It is used for transportation.
Explanation:
The Danube is a river in central Europe and the second longest in this continent (the first is the Volga), which flows mainly through ten countries (Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Romania, Bulgaria, Moldova and Ukraine) to finally flow into the Black Sea.
This river is of great importance for Eastern Europe because its channel serves as an international bridge for agricultural, fishing, tourism, commercial and industrial activities. In addition, the majority of the population that lives in its vicinity, depends on the water of the Danube to carry out its activities, which is why there is a large number of reservoirs and dams on its way.
Another important aspect is that the Danube has a high economic potential, due to its capacities for transport, commerce and tourism, so the use and use of its waters has been promoted.