北京时间3月22日，2015年世界女子冰壶世锦赛在日本札幌进行了最终的决赛，上届冠军瑞士队以5﹣3战胜加拿大队卫冕成功，近四届世锦赛第三次夺得冠军，加拿大队获得亚军，俄罗斯队获得第三名，中国获得第五名．小科在观看2015世界冰壶锦标赛时猜想：冰壶在冰面上的滑行距离，除了与离手时的速度大小、接触面的粗糙程度有关外，还可能与质量有关．

为了验证这一猜想，小科、小敏和小思做了如下实验（如图2所示）：在木块上加放数量不等的钩码后，让木块从O点静止滑下，记录木块和钩码的总质量m和它在水平面的滑行距离S，记录数据如下（各组在A点时初速度均相同）：

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    Mary is a student. She enjoys ____(run). Every morning, she starts to run near her home____ (介词) six o'clock. She also ____ (like) ball games. After school, she ____ (join) her classmates to play basketball. She ____ (eat) well too. She has three ____ (meal) at school. Her favourite food is ____(dumpling). But the dining hall is small with only ten ____ (table). The students are always ____(wait) there. Now it's time for dinner. Mary is ____ (walk) to the dining hall.

通过下列化学反应能达到目的是（　　）