题目

1．What is special about the Ariau Amazon Towers hotel?     A．You can sleep in tree houses．    B．You can choose any of the towers．     C．It is designed for big families．   D．Every room has a walkway． 2．For two persons spending a night in one of these hotels，they have to pay at least   .      A．$600      B．$111      C．$182       D．$636 3．Which website should you visit if you want to find out whether there is a hotel under the sea?     A．http：// www. ariautowers. com       B．http：// www．icehotel, cor若a，b是正常数，a≠b，x，y∈（0，+∞），则a2x+b2y≥(a+b)2x+y，当且仅当ax=by时取等号．利用以上结论，函数f（x）=2x+91-2x（x∈（0，12））取得最小值时x的值为（　　） A、1B、15C、2D、13