题干

下列有关物质的用途,与性质不对应的是(  )


A:铜丝用作电线,是因为铜具有导电性

B:洗涤剂能清洗餐具上的油污,是因为洗涤剂能溶解油污

C:二氧化碳用于灭火,是因为二氧化碳密度比空气大,且不燃烧也不支持燃烧

D:稀有气体能制成多种用途的电光源,是因为稀有气体在通电时能发出不同颜色的光

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B

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    Have you experienced times when you feel like you're under too much pressure? I think most of you will say yes. Actually, many things can strike us beyond our control. With an annoying mix of late trains, missed appointments and work deadlines, many of us are living in a constant state of stress. Experts warn, our modern lifestyles means that stress is almost continuous, and comes without the natural release that either fighting or fleeing might provide.____ Conditions vary from mood swings(情绪波动) to anxiety, irritability, nervousness and tiredness. In extreme cases, it can even cause headaches, muscle cramps, and digestive problems. But there are a number of things we can do to manage the symptoms.

    ____

    Balancing blood sugar is essential in lowering stress. To maintain its level, you can try to have one small meal every two-to-three hours that contains protein, for example, breakfast, lunch and dinner plus a mid-morning and mid-afternoon snack. In this case, your blood sugar will be steady.____

    Laugh as you like.

    ____Many studies show that laughter boosts our energy, decreases stress hormones, improves immunity and lessens pains. Try to find humor in life and engage in activities that make you laugh. Don't feel guilty about doing what you love. It will work its magic in your body.

    Schedule your workout timing.

    It could be the time, rather than the way that determines how effective your workouts would be.____Do energy-forming exercises like running or aerobics in the morning, and milder activities in the evening. Try a walk at the end of the day to calm your mind and stretch your muscles.

A. Eat little and often.

B. So will your mood swings.

C. Laughter is the best medicine.

D. These things are activated by laughing

E. The aim of exercise is to boost your energy.

F. Adapt your exercise routine to the biological clock.

G. Living with it can lead to a whole range of health problems.