题目

 右图是一种稀硫对Fe-Gr合金随Cr含量变化的腐蚀性实验结果，下列有关说法正确的是A.稀硫酸对Fe-Cr合金的腐蚀性比稀硫酸和稀盐酸的弱B.稀硝酸和铁反应的化学方程式是:Fe+6HNO3(稀)—Fe(NO3)3+3NO2↑+3H2OC.Cr含量大于13%时，因为三种酸中硫酸的氢离子浓度最大，所以对Fe-Cr合金的腐蚀性最强D.随着Cr含量增加，稀硫酸对Fe-Cr合金的腐蚀性减弱 13．假如你是李华，你的加拿大朋友Mike在与你同一城市的国际学校读书．你收到他的email了解到他最近因为一次考试没有考好而烦恼，请按照以下内容给Mike写一封回信．（1）宽慰（2）给予改进学习的建议（查找失败原因；向老师求助； 劳逸结合）（3）邀请周末去打篮球．注意：（1）字数100字左右；（2）可以适当增加细节，以使行文连贯；（3）开头和结尾已给出，不计入字数．Dear Mike，I'm sorry to hear that you failed in the last exam．But I have to remind you that nobody can win all the time．So you had better forget the unchangeable fact and focus more energy on future studies．（高分句型一）To guarantee success in the next exam，you are advised to do what I will tell you to．（高分句型二）First，find out the real reasons why you failed the exam．Only when you know where your mistakes are，will you know how to correct them．（高分句型三）Besides，it is wise to turn to your teachers for help．After all，they are experienced．Meanwhile，remember to strike the balance with studies and rest．Adequate sleep and proper exercise will certainly make it possible for you to keep energetic．How about playing football together this weekend？Surely we will have fun．Hoping everything will be fine with you．YoursLi Hua．