题干

某农民种植的小麦植株矮小,叶色发黄.根据所学的化学知识请你为他选择一种化肥(选氮肥、磷肥、钾肥),就使用化肥的利与弊分别谈谈你的观点(各答一点即可).

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氮肥能使农作物枝叶繁茂、叶色浓绿、提高产量;某农民种植的小麦植株矮小,叶色发黄,说明土壤中缺乏氮元素,因此选氮肥;
使用化肥的利处:促进粮食的增产;
使用化肥的弊处:容易造成土壤污染、水体污染、农产品污染等.

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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.