题干

由A、D、E、G四种微粒组成的复盐W的化学式为xAaDd•yE2D•zG.4.704g W溶于水得一澄清的弱酸性溶液,其中溶质总量为3.408g.同质量的W与5.13g氢氧化钡充分混匀后加热,生成的气体以足量铝盐溶液充分吸收得Al(OH)3 0.624g,加热后的残渣用水充分溶解后过滤,滤液以酚酞为指示剂用0.400mol/L H2SO4滴定至终点,用去H2SO4 15.0mL,滴定完毕后,溶液中检测不出任何金属离子和酸根离子;滤渣用硝酸洗涤时部分溶解,得一遇石炭酸显紫色的黄色溶液,依据推理和计算判断:
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根据短文内容, 从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

    Do you still remember the haze(雾霾)in the winter? So many people got terribly ill during or after the haze. ____Here is advice for you to protect yourself in hazy weather.

    Spend less time outdoors.This is the most effective way for self-protection in such bad weather.With PM2.5 increasing 103mg per cubic meter,residents will risk a 2.29% increase of death,which experts found out in 2012.If you have to get out,avoid riding bicycles.____

    Close your windows.Experts advice residents to avoid opening windows at home.If you have to ,avoid the time when smog is at its densest(浓的).____Besides,you can keep plants with broad leaves at home to absorb dust,and use air purifiers(清洁器).

    Smoke less.____In hazy weather,smoking would be even more harmful.Smokers are advised to keep their distance from cigarettes before the weather gets better.

    ____For example ,wear special masks outside to avoid breathing in PM2.5.Then take off your coat after getting indoors and keep it away from your other clean clothes,Don't forget to wash your face,rinse(漱)your mouth,and clean your nasal cavity(鼻腔)to clean the particulate matters(颗粒物)that fall on you.Last but not least,keep off stimulating(刺激性)foods.

A.Wear masks.

B.Pay attention to other daily things.

C.Also avoid rush hours,when pollutants will be denser.

D.That's because haze does harm to the health of people.

E.Cigarettes could cause more particulate matters,which are included in PM2.5 .

F.Take more fruits and vegetables instead,which are good for lung,spleen(脾)and kidney(肾).

G.For residents who use air-conditioner,make sure your apartment has enough oxygen indoors.