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Ehrlich's approach of systematically varying the chemical structure of synthetic compounds and measuring the effects of these changes on biological activity was pursued broadly by industrial scientists, including Bayer scientists Josef Klarer, Fritz Mietzsch, and Gerhard Domagk. This work, also based in the testing of compounds available from the German dye industry, led to the development of Prontosil, the first representative of the sulfonamide class of antibiotics. Compared to arsphenamine, the sulfonamides had a broader spectrum of activity and were far less toxic, rendering them useful for infections caused by pathogens such as streptococci. In 1939, Domagk received the Nobel Prize in Medicine for this discovery. Nonetheless, the dramatic decrease in deaths from infectious diseases that occurred prior to World War II was primarily the result of improved public health measures such as clean water and less crowded housing, and the impact of anti-infective drugs and vaccines was significant mainly after World War II.
Many deaths occurred before World War II due to what?
A: infectious diseases

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Kievan Rus' begins with the rule (882912) of Prince Oleg, who extended his control from Novgorod south along the Dnieper river valley in order to protect trade from Khazar incursions from the east and moved his capital to the more strategic Kiev. Sviatoslav I (died 972) achieved the first major expansion of Kievan Rus' territorial control, fighting a war of conquest against the Khazar Empire. Vladimir the Great (9801015) introduced Christianity with his own baptism and, by decree, that of all the inhabitants of Kiev and beyond. Kievan Rus' reached its greatest extent under Yaroslav I (10191054); his sons assembled and issued its first written legal code, the Rus' Justice, shortly after his death.
Which way did Prince Oleg extend his rule?
A: unanswerable

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Due to geographical proximity of the Central American countries to the U.S. which has powerful military, economic, and political influences, there were several movements and proposals by the United States during the 19th and 20th centuries to annex some or all of the Central American republics (Costa Rica, El Salvador, Guatemala, Honduras with the formerly British-ruled Bay Islands, Nicaragua, Panama which had the U.S.-ruled Canal Zone territory from 1903 to 1979, and formerly British Honduras or Belize since 1981). However, the U.S. never acted on these proposals from some U.S. politicians; some of which were never delivered or considered seriously. In 2001, El Salvador adopted the U.S. dollar as its currency, while Panama has used it for decades due to its ties to the Canal Zone.
When did Panama adopt the US Dollar as its currency?
A: unanswerable

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Lighthouse Point Park, a public beach run by the city, was a popular tourist destination during the Roaring Twenties, attracting luminaries of the period such as Babe Ruth and Ty Cobb. The park remains popular among New Haveners, and is home to the Five Mile Point Lighthouse, constructed in 1847, and the Lighthouse Point Carousel, constructed in 1916. Five Mile Point Light was decommissioned in 1877 following the construction of Southwest Ledge Light at the entrance of the harbor, which remains in service to this day. Both of the lighthouses and the carousel are listed on the National Register of Historic Places.
What notable New Haven attraction constructed in 1847 was located at Lighthouse Point Park?
A:
Five Mile Point Lighthouse