如图所示，中国的高铁建设被誉为是中国经济发展的奇迹，频频刷新世界纪录．2015年11月25日上午，中国国务院总理***邀请来华出席第四次中国﹣中东欧国家领导人会晤的中东欧国家领导人共同乘坐中国高铁，从苏州到上海，全程99Km，22分钟就到了．全程的平均速度为____ km/h．高铁高速运行时，以车上乘客为参照物，高铁是____ （选填“静止”或“运动”）的．

阅读下面短文，从各题所给的A、B、C、D四个选项中选出最佳选项。
B
Join Us for a Day at Sun Valley Amus ement Park

    Children aged 10 to 14 are invited to take part in the "Event of the Summer" at
Sun Valley Amusement Park, the most popular amusement park on the East Coast.
Sun Valley has more than 80 amusement rides. For sports lovers, there are
basketball courts, an indoor baseball field and climbing walls.
    No amusement park would be complete without a gift shop. Sun Valley
has two.
    You won't want to miss out on this day of fun. Join us at Sun Valley Amusement Park on July 14. Register (登记) early.
    • The cost of the trip is $ 25. This includes tickets and all rides.
    • We suggest that all children bring lunch.
    • Buses leave at 9.00 AM and return at 5.00 PM.
    • Rain Date: Wednesday, July 16.
    Register at the Children's Recreation Center at the Town Hall by July 3.
    A one-day registration will also be held on July 1 at the Brown School.
    For more information, call Jane Parks at 555-7267.

如果单项式﹣x³y^m+2与x³y的差仍然是一个单项式，则m=____．

胃部病变，外科医生可以将病人的胃全部切除，另用小肠再造一个胃。新造的胃比较小，病人要少吃多餐。人造胃能代替胃的部分功能，其原因是（    ）

下列关于生物技术的安全性和伦理问题的分析，不合理的观点是（　　）