John is a world traveler. Recently, he visited two countries, France and Germany. He noticed that in France they use atmosphere and Pascal as pressure units. In Germany they use torr as a pressure unit. Back in the United States, he noticed psi is used as a pressure unit. He needs to figure out how they correlate with each other. Which county is using a unit established by mesuring the rise of mercury, Germany or United States?
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Answer: Germany

John and Keith are neighbors. They have been pondering about how to communicate with each other in a doomsday scenario when all the electronic devices would be useless. They connected their houses with three ducts. One of the ducts is filled with air; they called it channel A. Another duct is filled with water; they called it channel B. And the last duct is filled with iron; they called it channel C. They can now transmit sound with these channels of communication; in case, disaster strikes. How many times faster is channel C than channel A, 4.3 times or 15 times?
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Answer: 15 times

Two friends were in college. Hank studied plate tectonics, while his buddy Alex studied Earth's atmosphere. They were both very fascinated by the subjects. Which student learned more about mantle convection?
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Answer:
Hank