题干

下列除杂方法(括号内为杂质)中正确的是(  )

A:二氧化碳(一氧化碳):通入氧气,点燃

B:硝酸铜溶液(硝酸银):加入足量的铜粉,过滤

C:碳酸钙固体(氯化钙):加入足量的水溶解,过滤、洗涤、干燥

D:氢氧化钠溶液(碳酸钠):加入适量的稀盐酸至不再产生气泡

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B,C

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    Life Is Beautiful is a 1997 Italian film directed by and starring Roberto Benigni. The film was a critical and financial success, winning Benigni the Academy Award for Best Actor as well as the Academy Award for Best Original Dramatic Score and the Academy Award for Best Foreign Language Film.

    In 1939 in the Kingdom of Italy, a bookstore keeper Guido, who is a Jew, falls in love with a local school teacher, Dora, who is to be engaged to a rich civil servant. Guido steals her from her engagement party on a horse. Soon they are married and have a son, Giosue.

    In 1945, Guido and his son are forced onto a train and taken to a concentration camp. Despite being a non-Jew, Dora demands to be on the same train to join her family. In the camp, Guido hides their true situation from his son, telling him that the camp is a complicated game in which Giosue must perform the tasks Guido gives him, earning him points;the first team to reach 1,000 points will win a tank.

    Guido uses this game to explain features of the concentration camp that would otherwise be scary for a young child. Despite being surrounded by the misery, sickness and death at the camp, Giosue does not question this fiction because of his father's convincing performance and his own innocence. Guido keeps the story right until the end when, in the chaos(混乱)of shutting down the camp as the Americans approach, he tells his son to stay in a small box until everybody has left, this being the final competition before the tank is his. Guido tries to find Dora, but is caught and killed by a Nazi soldier. As he is taken away to be shot, he maintains the fictions of the game by marching in a goose-step on purpose…