Question:
Triumph and Disaster: The 20th century saw a stupendous release of energies that had been pent up for the 250 years of Tokugawa isolation. By 1930 raw-material production had tripled the figure of 1900, manufactured goods had increased twelve-fold, and heavy industry was galloping towards maturity. Britain led the World War I Ailies in large orders for munitions, while Japan expanded sales of manufactured goods to Asian and other markets cut off from their usual European suppliers. Merchant shipping doubled in size and increased its income ten-fold as the European fleets were destroyed. Setbacks in the 1930s caused by the European postwar slump were only a spur to redouble efforts by diversifying heavy industry into the machine-making, metallurgical, and chemical sectors. Even the terrible 1923 Tokyo earthquake, which cost over 100,000 lives and billions of dollars, provided another stimulus due to the construction boom that followed. Riding the crest of this economic upsurge were the zaibatsu conglomerates — a dozen family-run combines, each involved in mining, manufacturing, marketing, shipping, and banking. These tightly controlled commercial pyramids were the true heirs to the old feudal structures. Japan's progress toward parliamentary democracy was halted in the 1930s by the growing nationalism being imposed on government by the generals and admirals. They proclaimed Japan's mission to bring progress to its backward Asian neighbors in language not so very different from that of the Europeans in Africa or the US in Latin America. After the Russian Revolution of 1917, the Soviet Union was regarded as a major threat to Japan's security, and the army felt it needed Manchuria and whatever other Chinese territory it could control as a buffer against Russian advances. In 1931 the Japanese occupied Manchuria. And then in 1937, with the popular support of ultra-right-wing groups, the army overrode parliamentary resistance in Tokyo and went to war against the Chinese Nationalists. By 1938, they held Nanking, Hankow, and Canton. Japanese expansionist policies were leading to direct confrontation with the West. Japan hoped that war in Europe would divert the Soviet Union from interference in East Asia, giving Japan a free hand both in China and, through its alliance with Germany, in French IndoChina after the defeat of France. The US responded to the Japanese invasion of IndoChina with a trade and fuel embargo, cutting off 90 percent of Japan's supplies. The result was the attack on the American fleet at Pearl Harbor (7 December 1941) and total war.  After reading the above, is "The Japanese government" the correct answer to the question "What country held possession of Nanking, Hankow, and Canton by 1938?"?

Answer:
yes


Question:
Right after the Pentagon was hit, NEADS learned of another possible hijacked aircraft. It was an aircraft that in fact had not been hijacked at all. After the second World Trade Center crash, Boston Center managers recognized that both aircraft were transcontinental 767 jetliners that had departed Logan Airport. Remembering the "we have some planes" remark, Boston Center guessed that Delta 1989 might also be hijacked. Boston Center called NEADS at 9:41 and identified Delta 1989, a 767 jet that had left Logan Airport for Las Vegas, as a possible hijack. NEADS warned the FAA's Cleveland Center to watch Delta 1989. The Command Center and FAA headquarters watched it too. During the course of the morning, there were multiple erroneous reports of hijacked aircraft. The report of American 11 heading south was the first; Delta 1989 was the second. NEADS never lost track of Delta 1989, and even ordered fighter aircraft from Ohio and Michigan to intercept it. The flight never turned off its transponder. NEADS soon learned that the aircraft was not hijacked, and tracked Delta 1989 as it reversed course over Toledo, headed east, and landed in Cleveland. But another aircraft was heading toward Washington, an aircraft about which NORAD had heard nothing: United 93. United Airlines Flight 93 FAA Awareness. At 9:27, after having been in the air for 45 minutes, United 93 acknowledged a transmission from the Cleveland Center controller. This was the last normal contact the FAA had with the flight. Less than a minute later, the Cleveland controller and the pilots of aircraft in the vicinity heard "a radio transmission of unintelligible sounds of possible screaming or a struggle from an unknown origin." The controller responded, seconds later: "Somebody call Cleveland?"This was followed by a second radio transmission, with sounds of screaming.  After reading the above, is "The Pentagon and the World Trade Center" the correct answer to the question "Which buildings that were hit by aircraft?"?

Answer:
yes


Question:
Sound waves are mechanical waves. They can travel only through matter. They cannot travel through empty space. This was demonstrated in the 1600s by a scientist named Robert Boyle. Boyle placed a ticking clock in a sealed glass jar. The clock could be heard ticking through the air and glass of the jar. Then Boyle pumped the air out of the jar. The clock was still running, but the ticking could not be heard. Thats because the sound couldnt travel without air particles to transfer the sound energy. Is there any other place where sound cannot be heard? Here is a hint: is there any other place that does not have air molecules? Thats right, in space sound cannot be transferred. So can astronauts hear each other? Yes, they can, because they are in enclosed space stations or pressurized suits.In both cases, they are surrounded by air molecules. If they left their space ship and did not use their electronics, they would not be able to hear each other. Next time you watch a science fiction movie, think about this factoid. When spaceships are destroyed by hostile alien beings, there would be no sound heard. Sound waves can travel through many kinds of matter.  After reading the above, is "Mechanical waves can only travel through matter." the correct answer to the question "Why can't you hear in the vacuum?"?

Answer:

yes