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关于声音的说法，错误的是（　　）。

A.声音在障碍物表面会产生反射
B.声波会绕过障碍物传播
C.声波在空气中的传播速度与频率有关
D.声波传播速度不同于质点的振动速度
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Maria Mitchell（1818-1889）,the first woman astronomer（天文学家）in the United was born in Nantucket, Massachusetts. Her parents valued education and insisted on giving same quality of education that boys received.
Her father, William Mitchell, was an astronomer and teacher himself. When he built his own school, Maria became a student and also a teaching assistant to him. At home, Maria's father taught her to watch the stars and other 'natural objects in space using his personal telescope（望远镜）．
Later she went to work at the library of the Nantucket Atheneum. Over the next twenty years, she further developed her interest in reading as many books as she could. She spent her nights watching the sky closely with her father.
On October 1,1847, Maria discovered a comet（彗星）by merely using a two-inch telescope. Some years before, King Frederick VI of Denmark had set up prizes to each discoverer of a "telescopic comet ". The prize was to be given to the "first discoverer" of each such comet because comets were often discovered by more than one person.
There was once a question of who should be the winner. As the story goes, Francesco de Vico had discovered the same comet two days later, but had reported it to the European official organization first. However, after some discussion this was settled in Mitchell's favor. She won the prize in 1848 and became a big name the world over. The comet was named "Miss Mitchell's Comet".
What problem did Maria meet with in winning the prize? （　　
A.Shenamedthecometonherown
B.Shedidnotusetherequiredtelescope
C.Shedidnotreportherdiscoveryintime
D.Shediscoveredthecometwithherfather
单项选择题
用数字万用表直流电压挡测量 ECU 的 1 号脚电压。
A、有 12V 电压
B、无 12V 电压
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基金公司总经理对（　　）负责，根据公司章程和董事会授权行使职权，领导和主持公司的管理工作，负责公司的日常经营，并由若干名副总经理等管理层成员提供协助。
A.董事会
B.监事会
C.股东会
D.督察长
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