Who prepared the first effective vaccine against polio?
Answer: D
Jonas Salk invented the polio vaccine.
His injected vaccine of 1955 used killed virus, and he refused to patent it, asking who could patent the sun. Albert Sabin's oral vaccine, using live attenuated virus, followed and is the one used in mass campaigns.
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Who invented the modern periodic table arranged by atomic number ?
Answer: D
Correct answer: Henry Moseley
Mendeleev arranged the elements by atomic weight and famously left gaps for undiscovered ones, but the anomalies in his ordering were resolved only when Henry Moseley showed in 1913 that atomic number is the correct organising principle.
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Who is credited with inventing the first mechanical calculator, the Pascaline ?
Answer: A
Correct answer: Blaise Pascal
Pascal built the Pascaline in 1642, at the age of nineteen, to help his father with tax accounts. It could add and subtract directly, and Leibniz later extended the principle to multiplication with his stepped reckoner.
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Who Invented Elevator Safety Brake ?
Answer: B
Elisha G. Otis invented it.
His device of 1852 used a wagon spring that engaged ratchets on the guide rails the moment rope tension was lost. He demonstrated it at the New York Crystal Palace in 1854 by having the rope cut while standing on the platform.
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Which app to locate board examination centres for students was launched by which body?
Answer: A
It was launched by the CBSE.
The Central Board of Secondary Education released an app to let candidates find their examination centre by entering their roll number, showing the route and distance.
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What game was first produced by the Southern Novelty Company in Baltimore, Maryland, in 1892?
Answer: C
It was the Ouija board.
Elijah Bond patented it in 1891 and the Kennard Novelty Company, later the Southern Novelty Company of Baltimore, produced it. The name is usually said to combine the French and German words for yes.
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What is Charles Babbage (1792-1871) remembered for?
Answer: A
He is remembered for computers.
Charles Babbage designed the Difference Engine and then the Analytical Engine, which had a store, a mill, punched-card input and conditional branching - the essentials of a computer, a century before one was built. Neither was completed in his lifetime.
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Who invented Radar
Answer: C
Robert Watson-Watt invented radar.
Asked in 1935 whether radio waves could be used to destroy aircraft, he showed instead that they could detect them, and his Daventry experiment led to the Chain Home stations that gave Britain warning in 1940.
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Who Discovered The Nucleus of a Cell?
Answer: C
Robert Brown discovered it.
The Scottish botanist described the nucleus in orchid cells in 1831 and gave it that name. He is also remembered for Brownian motion, the random jitter of pollen grains in water that Einstein later explained.
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Who is the inventor of printing press?
Answer: A
Johannes Gutenberg invented it.
At Mainz in the 1440s he combined movable metal type cast in a hand mould, oil-based ink and a screw press. His Bible of about 1455 was the first substantial European book printed with movable type.
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