Problem: Nasser's involvement in political activity increased throughout his school years, such that he only attended 45 days of classes during his last year of secondary school. Despite it having the almost unanimous backing of Egypt's political forces, Nasser strongly objected to the 1936 Anglo-Egyptian Treaty because it stipulated the continued presence of British military bases in the country. Nonetheless, political unrest in Egypt declined significantly and Nasser resumed his studies at al-Nahda, where he received his leaving certificate later that year.
How many days did Nasser attend classes in his senior year?
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Answer: 45


Problem: The Neapolitan style has an almond-shaped body resembling a bowl, constructed from curved strips of wood. It usually has a bent sound table, canted in two planes with the design to take the tension of the 8 metal strings arranged in four courses. A hardwood fingerboard sits on top of or is flush with the sound table. Very old instruments may use wooden tuning pegs, while newer instruments tend to use geared metal tuners. The bridge is a movable length of hardwood. A pickguard is glued below the sound hole under the strings. European roundbacks commonly use a 13-inch scale instead of the 13.876 common on archtop Mandolins.
What are the Neapolitan mandolin made of?
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Answer: metal strings


Problem: Commercial solar water heaters began appearing in the United States in the 1890s. These systems saw increasing use until the 1920s but were gradually replaced by cheaper and more reliable heating fuels. As with photovoltaics, solar water heating attracted renewed attention as a result of the oil crises in the 1970s but interest subsided in the 1980s due to falling petroleum prices. Development in the solar water heating sector progressed steadily throughout the 1990s and growth rates have averaged 20% per year since 1999. Although generally underestimated, solar water heating and cooling is by far the most widely deployed solar technology with an estimated capacity of 154 GW as of 2007.
Since 1999, what average rate has the solar water heating sector progressed at?
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Answer:
20% per year