题目

（7分）有A、B、C、D四种无色气体， ①A能使湿润的红色石蕊试纸变蓝； ②一定条件下，A可以与B反应生成C，C遇空气变为红棕色； ③D与A混合生成白烟； ④D的浓溶液与软锰矿(主要成分是MnO2)在加热条件下反应可制取黄绿色气体E；按要求回答下列问题： （1）写出A与B生成C 的化学方程式                                   ； （2）写出④的离子方程式                                 ； （3）气体E有毒，实验室一般用 � Directions：Read the following passage．Complete the diagram by using the information for the passage．Write NO MORE THAN 3 WORDS for each answer． 　　While it is impossible to live completely free of stress, it is possible to prevent stress as well as reduce its effect when it can' t be avoided．The US Department of Health and Human Services offers the following suggestions for ways to deal with stress． 　　Try physical activity． 　　When you are nervous, angry or upset, try releasing the pressure through exercise or physical activity．Running, walking, playing tennis, or working in your garden are just some of the activities you might try． 　　Take care of yourself． 　　You should make every effort to eat well and get enough rest．If you easily get angry and cannot sleep well enough, or if you're not eating properly, it will be more likely that you will fall into stressful situations．If stress repeatedly keeps you from sleeping, you should consult a doctor． 　　Make time for yourself． 　　Schedule time for both work and entertainment．Don' t forget, play can be just as important to you over－all well－being as work．You need a break from your daily routine to just relax and have fun．Go window－shopping or work on a hobby．Allow yourself at least a half hour each day to do something you enjoy． 　　Make a list of the things you need to do． 　　Stress can result from disorganization and a feeling that "there's so much to do, and not enough time．Trying to take care of everything at once can be too much for you and as a result, you may not achieve anything．Instead, make a list of everything you have to do, then do one thing at a time．Set out to do the most important tasks first．Check off each task as it is completed． Title：How to 　　1