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    Come and see the Indian elephants and tigers from America. The koalas are waiting to meet you, and the monkeys from Thailand are waiting to throw things at you. The cute dogs from Australia are waiting to laugh at you, and the giraffes from Zambia are waiting to look down on you.
Tickets (票)                                           Time
Adult (成人): $ 6                                   June 1~ June 2
Children: Free                                       9:00 am.~ 7:00 pm.
Keep the park clean!
    Do not touch (触摸), give food or go near the animals!

将抛物线y=2x²向下平移1个单位，得到的抛物线是(    )

抛物线y＝x²－4x－7的顶点坐标是(   )