问题
单项选择题
适用于广场、飞机场、海港等大面积照明的电光源是( )。
A．氙灯
B．纳灯
C．水银灯
D．荧光灯
答案
参考答案：A
解析：氙灯是采用高压氙气放电产生很强白光的光源，和太阳光相似，故显色性很好，发光效率高，功率大，有“小太阳”的美称，故适用于广场、飞机场、海港等大面积的照明。
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适用于广场、飞机场、海港等大面积照明的电光源是( )。
A．氙灯
B．纳灯
C．水银灯
D．荧光灯
参考答案：A
解析：氙灯是采用高压氙气放电产生很强白光的光源，和太阳光相似，故显色性很好，发光效率高，功率大，有“小太阳”的美称，故适用于广场、飞机场、海港等大面积的照明。
Harvard University named historian Drew Gilpin Faust as its first female president on Sunday, ending a lengthy and secretive search to find a successor（接任者）to Lawrence Summers . The seven-member Harvard Corporation elected Faust, a noted scholar on History of the American South and dean of Harvard’s Radcliffe Institute for Advanced Study, as the university’s 28th president. “This is a great day, and a historic day for Harvard,” James R. Houghton, chairman of the presidential search committee, said in a statement. “Drew Faust is an inspiring and accomplished leader, a superb scholar, a dedicated teacher, and a wonderful human being.” Her selection is noteworthy given the heated debates over Summers’ comments that genetic differences between the sexes might help explain the lack of women in top science jobs. Faust has been dean of Radcliffe since 2001, two years after the former women’s college was combined into the university as a research center with a mission to study gender issues. Some professors have quietly groused that the 371-year-old university is appointing a fifth president who is not a scientist. No scientist has had the top job since James Bryant Conant retired in 1953; its last four have come from the fields of classics, law, literature and economics.
小题1:Which might be the best title for the passage?
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