The Atlantic Ocean is the answer to the question.
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.
Explanation: climatology is not a branch of human geography.
C) This is the right answer.
If the coast-to-coast distance is about 2900 miles, it will take about ...
... (2900 mi)/(186000 mi/s) ≈ 15.6 ms
for the signal to travel coast-to-coast at light speed.
_____
There are time delays due to the amplifiers and repeaters required in the path, and due to the fact that the signals don't actually travel at the speed of light in a wire.
A test of internet speed between Seattle and Washington, DC shows a round-trip time of about 87 ms when traffic is light. Modern communication channels tend to be faster than the telegraph (especially when measured in words per minute).
