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    New Sciencenter Featured Exhibition: Ocean Bound!

    Opening weekend

    Member Preview: Friday, February 3, 6—8 pm

    Public Opening: Saturday, February 4, 10 am — 5 pm

    Start a journey through watersheds to see how everyone's actions affect the health of our ocean. Enjoy interacting with 3D watershed models, piloting a full-size submersible from mountain stream to ocean, guiding water safely through a hazardous maze, diverting pollutants as they travel through storm-water drains, playing with early education exhibits inside a clubhouse, and many more engaging interactive exhibits.

    Showtime! Plant and Animal Double-Takes

    Saturday, January 21, 2 pm

    Have you ever looked at a living thing and wondered, Is that a plant or an animal? Join Sciencenter educators Julie Yurek and Sarah Cox to look into species that make you take a second look. Explore the surprising differences between these plants and animals.

    Showtime! Solar Power Goes Nano

    Saturday, February 11, 2 pm

    Did you know scientists are using nanotechnology to store solar energy? Learn about solar power and the emerging use of hydrogen fuel cells. Justin Sambur, NSF Postdoctoral Research Associate at Cornell's Department of Chemistry and Chemical Biology, will demonstrate a model race car that uses a hydrogen fuel cell kit powered by solar energy.

    Special Showtime! Presentation: Animal Adaptations for Winter

    Wednesday, February 22, 1 pm

    Have you ever wondered how animals survive in winter? Join Emma Brofsky of Cornell's Naturalist Outreach Program to explore animal adaptations for winter and learn how biology helps animals cope with cold weather, food shortages, and limited habitats. Touch animal pelts and do a hands-on activity on animal insulation.

《史记》记述了从黄帝到汉武帝时期的史事，是我国第一部纪传体通史。下列人物在《史记》中应该没有记载的是 (     )

已知西瓜的染色体数目2n＝22，请根据下面的西瓜育种流程回答有关问题：

根据短文内容，回答下列问题。
   Linda and Mary are good friends. Linda is thirteen. She comes from the U.S.A. Mary is twelve. She's from London(伦敦). They study in the same school, but in different classes. Linda's father teaches English in a middle school. Her mother drives a car. Mary's mother works in an office. Her father is a doctor. Linda can speak English, French(法语) and a little Chinese. Linda's mother likes cooking. She likes eating rice. But Linda' s father doesn't. He likes drinking milk and eating bread. Mary's mother doesn't like cooking. But she likes doing some shopping. She can make nice skirts and dresses. Mary's father likes doing housework(家务).