题干

用化学符号填空:

①两个铁离子____ ,②硫酸中硫元素的化合价____ ,③表示的是____ .

(2)汽油中加入适量的乙醇作为汽车燃料,可适当节省石油资源,并减少污染,写出乙醇在空气中燃烧的化学方程式____ .

(3)在一个密闭容器中有A、B、C、D四种物质,在一定条件下充分反应,测得数据如下:

物质

A

B

C

D

反应前的质量/g

6.4

3.2

4.0

2.8

反应后的质量/g

5.2

待测

7.2

2.0

反应后待测的B的质量是____ 克,该反应所属的基本反应类型是____

(4)现有铁、氧化铜、稀盐酸、氢氧化镁、氢氧化钠溶液、硫酸铜溶液六种物质,两两混合能发生的反应有____ 个.

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    If you've been diagnosed with high blood pressure, you might be worried about taking medication to bring your numbers down. Chronic(慢性的) stress may contribute to high blood pressure. More research is needed to determine the effects of chronic stress on blood pressure. Occasional stress also can contribute to high blood pressure if you react to stress by eating unhealthy food, drinking alcohol or smoking.

    Take some time to think about what causes you to feel stressed, such as work, family, finances or illness. Once you know what's causing your stress, consider how you can rid or reduce stress. If you can't rid all of your stressors, you can at least handle them in a healthier way. Try to:

    Change your expectations. For example, plan your day and focus on your strengths. Avoid trying to do too much and learn to say no. Understand there are some things you can't change or control, but you can focus on how you react to them.

    Focus on issues you can control and make plans to solve them. If you are having an issue at work, try talking to your manager. If you are having a conflict with your kids or spouse, take steps to resolve it.

    Avoid stress triggers(诱因). Try to avoid triggers when you can. For example, if rush-hour traffic on the way to work causes stress, try leaving earlier in the morning, or take public transportation. Avoid people who cause you stress if possible.

    Make time to relax and to do activities you enjoy. Take time each day to sit quietly and breathe deeply. Make time for enjoyable activities or hobbies in your schedule, such as taking a walk, cooking or volunteering.

    Practice gratitude. Expressing gratitude to others can help reduce your stress.

    If you successfully control your blood pressure with reducing stress, you might avoid, delay or reduce the need for medication.