阅读图文材料，结合所学地理知识回答问题。
    材料 2013年10月2日，中国国家主席习近平从北京启程，对印度尼西亚和马来西亚进行国事访问并出席了在印尼巴厘岛举行的亚太经合组织(APEC)第二十一次领导人非正式会议。

如图，在平面直角坐标系中，抛物线与轴的交点为，与轴的交点分别为，，且，直线轴，在轴上有一动点过点作平行于轴的直线与抛物线、直线的交点分别为、．
求抛物线的解析式；
当时，求面积的最大值；
当时，是否存在点，使以、、为顶点的三角形与相似？若存在，求出此时的值；若不存在，请说明理由．

某中学为了了解七年级男生入学时的跳绳情况，随机选取名刚入学的男生进行个人一分钟跳绳测试，并以测试数据为样本，绘制出部分频数分布表和部分频数分布直方图（如图所示）.根据图表解答.下列问题：

_________，__________；

这个样本数据的中位数落在第________组；

若七年级男生个人一分钟跳绳次数时成绩为优秀，则从这名男生中任意选一人，跳绳成绩为优秀的概率为多少？

若该校七年级入学时男生共有人，请估计此时该校七年级男生个人一分钟跳绳成绩为优秀的人数.

组别	次数	频数（人数）
第组
第组
第组
第组
第组
第组

已知反比例函数的图象经过点，则当时，         .

    It came as something of a surprise when Diana, Princess of Wales, made a trip to Angola in 1997, to support the Red Cross’s campaign for a total ban on all anti-personnel landmines. Within hours of arriving in Angola, television screens around the World were filled with images of her comforting victims injured in explosions caused by landmines. “I knew the statistics,” she said. “But putting a face to those figures brought the reality home to me; like When I met Sandra, a 13-year-old girl who had lost her leg, and people like her.”
    The Princess concluded, with a simple message: “We must stop landmines”. And she used every opportunity during her visit to repeat this message.
    But, back in London, her views were not shared by some members of the British government, which refused to support a ban on these weapons. Angry politicians launched an, attack on the Princess in the press. They described her as “very ill-informed” and a “loose cannon (乱放炮的人).”
The Princess responded by brushing aside the criticisms: “This is a distraction (干扰) we do not need. All I’m trying to do is help.”
    Opposition parties, the media and the Public immediately voiced their support for the Princess. To make matters worse for the government, it soon emerged that the Princess’s trip had been approved by the Foreign Office, and that she was in fact very well-informed about both the situation in Angola and the British government’s policy regarding landmines. The result was a severe embarrassment for the government.
    To try and limit the damage, the Foreign Secretary, Malcolm Rifkind, claimed that the Princess’s views on landmines were not very different from government policy, and that it was “working towards” a worldwide ban. The Defense Secretary, Michael Portillo, claimed the matter was “a misinterpretation or misunderstanding.”
    For the Princess, the trip to this war-torn country was an excellent opportunity to use her popularity to show the world how much destruction and suffering landmines can cause.She said that the experience had also given her the Chance to get closer to people and their problems.