Problem: Vacuum:

To continue evacuating a chamber indefinitely without requiring infinite growth, a compartment of the vacuum can be repeatedly closed off, exhausted, and expanded again. This is the principle behind positive displacement pumps, like the manual water pump for example. Inside the pump, a mechanism expands a small sealed cavity to create a vacuum. Because of the pressure differential, some fluid from the chamber (or the well, in our example) is pushed into the pump's small cavity. The pump's cavity is then sealed from the chamber, opened to the atmosphere, and squeezed back to a minute size.

How is a vacuum created in the atmosphere?
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A: unanswerable

Problem: Sumer:

The Sumerians developed a complex system of metrology c. 4000 BC. This advanced metrology resulted in the creation of arithmetic, geometry, and algebra. From c. 2600 BC onwards, the Sumerians wrote multiplication tables on clay tablets and dealt with geometrical exercises and division problems. The earliest traces of the Babylonian numerals also date back to this period. The period c. 2700 2300 BC saw the first appearance of the abacus, and a table of successive columns which delimited the successive orders of magnitude of their sexagesimal number system. The Sumerians were the first to use a place value numeral system. There is also anecdotal evidence the Sumerians may have used a type of slide rule in astronomical calculations. They were the first to find the area of a triangle and the volume of a cube.

What did the Sumerians a complex system of around 4000 BC?
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A: metrology

Problem: Himachal Pradesh:

Himachal Pradesh is famous for its abundant natural beauty. After the war between Nepal and Britain, also known as the Anglo-Gorkha War (18141816), the British colonial government came into power and the land now comprising Himachal Pradesh became part of the Punjab Province of British India. In 1950, Himachal was declared a union territory, but after the State of Himachal Pradesh Act 1971, Himachal emerged as the 18th state of the Republic of India. Hima means snow in Sanskrit, and the literal meaning of the state's name is "In the lap of Himalayas". It was named by Acharya Diwakar Datt Sharma, one of the great Sanskrit scholars of Himachal Pradesh.

What came into power after the war between Himachal and Sanskrit?
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A: unanswerable

Problem: Botany:

Inheritance in plants follows the same fundamental principles of genetics as in other multicellular organisms. Gregor Mendel discovered the genetic laws of inheritance by studying inherited traits such as shape in Pisum sativum (peas). What Mendel learned from studying plants has had far reaching benefits outside of botany. Similarly, "jumping genes" were discovered by Barbara McClintock while she was studying maize. Nevertheless, there are some distinctive genetic differences between plants and other organisms.

What other plant was used in the discovery of different genes?
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A:
maize