下列纬线圈中长度最长的是（　　）

下列离子方程式与所述事实相符且正确的是(　　)
①将氯气溶于水制备次氯酸：Cl₂＋H₂O===2H^＋＋Cl^－＋ClO^－
②漂白粉溶液在空气中失效：ClO^－＋CO₂＋H₂O===HClO＋HCO₃^－
③向NaAl(OH)₄溶液中通入过量CO₂制Al(OH)₃：Al(OH)₄^－＋CO₂===Al(OH)₃↓＋HCO₃^－
④将铁粉加入稀H₂SO₄中：2Fe＋6H^＋===2Fe^3＋＋3H₂↑
⑤用浓盐酸与MnO₂反应制取少量氯气：MnO₂＋2H^＋＋2Cl^－===Mn^2＋＋Cl₂↑＋2H₂O
⑥用浓盐酸酸化的KMnO₄溶液与H₂O₂反应，证明H₂O₂具有还原性：2MnO₄^－＋6H^＋＋5H₂O₂===2Mn^2＋＋5O₂↑＋8H₂O

  硫酸铵和氯化钾是化工生产的副产品，直接作为肥料使用会使土壤酸化或影响作物的生长，工业上往往将氯化钾转化为无氯钾肥．如图1是硫酸铵等几种盐的溶解度曲线．回答下列问题：

下列对月球景观的描述正确的是(  )

阅读短文，从下面方框中选出10个词，并用其正确形式填入下列短文中，使短文意思正确、通顺。（每词限用一次）

people   cut    easy   hurt   wet  difference  much  anyone   unlucky  well   take  clean

    If you don't keep yourself warm enough, winter can be a time to have an illness. During the winter months, people____ get colds and flu(流感). Many people think they are the same, but they are____.

    Colds can stay with you for up to a week. You will have a running nose, a sore throat, a headache, a cough and a fever.

    Flu is ____ serious. You will feel sick very quickly. You will have a fever and a headache. Your body will ____ and become weak. This could last for up to four weeks.

    Is there any way to keep yourself away from colds; rod flu? Staying clear of(避开) ____with colds or flu may work. Try not to touch(触摸) your nose or eyes if you have been close to ____ who has a cold. Wash your hands, especially after ____ your nose. Going out with ____ hair can also give you a cold!

    If you catch a cold or flu, go to bed and rest. Doing this will help you get ____. Drink lots of water. Stay in a warm, well-aired room. If you have a headache, or your muscles(肌肉) hurt, don't forget ____ some medicine.