阅读下文，完成后面练习题

    梁惠王曰：“寡人之于国也，尽心焉耳矣。河内凶，则移其民于河东，移其粟于河内；河东凶亦然。察邻国之政，无如寡人之用心者。邻国之民不加少，寡人之民不加多，何也？” 

孟子对曰：“王好战，请以战喻。填然鼓之，兵刃既接，弃甲曳(yè)兵而走。或百步而后止，或五十步而后止。以五十步笑百步，则何如？” 

    曰：“不可！直(zhǐ)不百步耳，是亦走也。” 

    曰：“王如知此，则无望民之多于邻国也。不违农时，谷不可胜食也;数（cù）罟（gǔ）不入洿（wū)池，鱼鳖不可胜食也;斧斤以时入山林，材木不可 胜用也。谷与鱼鳖不可胜食，材木不可胜用，是使民养生丧（sāng）死无憾也。养生丧死无憾，王道之始也。五亩之宅，树之以桑，五十者可以衣（yì）帛 矣。鸡豚狗彘(zhì)之畜（xù），无失其时，七十者可以食肉矣。百亩之田，勿夺其时，数口之家可以无饥矣；谨庠（xiáng）序之教，申之以孝悌 (tì)之义，颁白者不负戴于道路矣。七十者衣帛食肉，黎民不饥不寒，然而不王(wàng）（称王）者，未之有也。狗彘食人食而不知检，涂有饿莩 （piǎo）而不知发，人死，则曰：‘非我也，岁也。’是何异于刺人而杀之，曰：‘非我也，兵也？’王无罪岁，斯天下之民至焉。” 

①该溶液的焰色反应呈现出紫色．

②取10mL该溶液于试管中滴加Ba（NO₃）₂溶液，加稀硝酸酸化后过滤得到0.03mol白色沉淀，向滤液中加入AgNO₃溶液未碱沉淀产生．

③另取10mL该溶液于试管中，滴加NaOH溶液产生白色沉淀，当沉淀增加到一定量后开始产生气体，最后沉淀完全溶解，并且随NaOH溶液的加入，沉淀和气体的变化关系如图所示：

阅读下面的说明文，回答后面小题。
      沿海和岛屿居民中的寿星为什么特别多
      目前世界上平均寿命最长的国家是瑞典、冰岛、荷兰、挪威和日本。我们会很容易发现，这些国家都是沿海国家或岛国。科学家研究表明，沿海地区的环境确实有利于人体健康。
      滨海地区面向海洋，海洋空气较内陆少受污染，空气中含有较少的有毒物质，而含有较多的人体必需的微量元素。空气中负离子特别丰富，可以改善人肺的换气功能，增加氧的吸收量和二氧化碳的呼出量，调节中枢神经系统的兴奋和抑制状态，刺激造血系统功能等等。这些对人体健康都十分有利。
滨海地区气候—般较温和湿润，即使北欧国家气候较寒冷，海滨地区—年中气温变化也不大，不像大陆性气候那样暴冷暴热，这对人的新陈代谢有好处。如我国海南岛，四面环海，气候温和，长夏无冬，秋春相连，空气新鲜，全年平均气温为23—25℃，而最高气温在35℃以上的天数却比大陆少10-20天。海南岛的百岁寿星比例高达1／100000，远高于全国的0.37／100000。同样，上海的长兴岛，也是夏无酷暑，冬无严寒，四面环水，四季常绿，空气中负离子浓度较高，岛上居民长寿者较多。
      滨海地区海产品丰富，食物种类繁多，有利于调节人体的营养平衡。如日本诲产品的人均消费量是世界上最多的，日本人的人均寿命也名列世界前茅。我国海南岛上的居民，饮食以大米、薯类、瓜菜和诲产品为主，很少吃动物脂肪。这种饮食结构和习惯也有利于长寿。
      滨海区居民能较充足地得到生命必需的元素，海水中有毒元素浓度很低，使他们能最大限度地降低非必需元素在人体内的累积速度。比如，专家们对上海市长兴岛人的头发进行了测定，发现锰和锌含量普遍高，铜、镍等微量元素含量馆低。医学家认为，锰和锌多对人体有利，铜、镍过量对人体不利。长兴岛独特的地理环境，使岛上的水源、土壤及农作物中均呈现锰、锌含量高，而铜、镍含量低的状况。
      世界上的高寿区除了在海滨、海岛之外，还有不少在宁静秀丽的山村，或寒带的内陆区。但是，如果将世界的居民分成滨海区与内陆区来比较，显然滨海区的长寿者更多。
（选自《十万个为什么》）

根据短文理解，选择正确答案。

    My writing career began ten years ago with my articles published locally and nationally. As a beginning writer, I was happy to be on my way, writing and learning as much as I could . With two little kids underfoot, as well as working full-time, it was really difficult to make time for writing, but I managed.

    Readers told me they laughed, cried or were inspired by my articles. But they didn't know what was really going on behind the typewriter. I was not a happy mommy, and found it difficult to enjoy the everyday little things in life. In short, I was not a happy person.

    I realized I had to make some changes. I started walking every morning. It cleared my head, allowed me time to think, gave me fresh air, and made me feel invigorated (精神焕发） and healthy. I was eating wisely, and the weight started to go. I started a new job, joined a monthly writing chapter，and was determined to keep up my walking. Finding the balance was sometimes difficult. But I was determined to fit in writing time because it made me happy. Sure I loved to watch the news and have my tea, but that wasn't what made me truly happy.

    My own happiness has shown through my family, my job performance and my attitude towards challenging situations. I again have readers telling me the effect my writing has had on them, with some able to get on with their own writing because of my articles.

    It was up to me to make it happen—my own happiness. One step at a time-one word at a time. And I did it.