<span> Hitler marched his troops into the Rhine, the Sudetenland, the rest of Czechoslovakia, and Austria over the protests of Britain, France, and the US. On Sept. 1, 1939, Nazi Germany invaded Poland, thereby starting WW2 in Europe. The Poles fought valiantly against Hitler's forces; when they took refuge behind the Vistula River, and it seemed they could hold on until the arrival of the British and French, Stalin entered the war and invaded Poland from the east. About 2 weeks later it was all over for the Poles. </span>
<span>Stalin also invaded Finland on the flimsy pretext of protecting his northern frontier. The Finns, although outnumbered and outgunned, held off the Soviets for several months. </span>
<span>Japan annexed Korea in 1910. The militarists of Japan also invaded Manchuria (China) in 1933, trying to create what they called the "Greater East Asia Co-Prosperity Sphere." In their delirious minds, they thought that Asia would thrive if all of it was under their rule. The rest of Asia disagreed. Japanese brutality in Manchuria caused the US to enact a trade embargo against Japan. The Japanese used the embargo as an excuse for the attack on Pearl Harbor on Dec. 7, 1941, thereby precipitating America's entry into WW2. </span>
The correct answer is - 25 miles.
The journey/postal/communication relay system established in the Mongol Empire had stations set on approximately 25 miles, though there were variations from around 20 to around 30 miles.
This system was set up because the empire was enormous, so the quick travel of information was key for its functioning and proper organization.
The system, known as yam or ortoo, was very simple but very effective. For the means of travel the horse was the animal that was used, and the Mongols estimated the distance at which a single horse can be giving its maximum in speed, so they put up stations at distances where the horse's speed will start to decline because of exhaustion. The rider of the horse was either giving the message to another rider, or he was taking food and water with him, as well as a new, rested horse, and continued to the other station.
Answer: Johannes Kepler
Explanation: Johannes Kepler (Weil der stadt, December 27th, 1571 - Regensburg, November 15th, 1630), a key figure in the scientific revolution, was a German astronomer and mathematician; known primarily for his laws on the movement of planets in their orbit around the sun. He was a collaborator of Tycho Brahe, whom he replaced as imperial mathematician of Rudolph II.