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用内置有螺旋状铜丝的胶头滴管小心吸取一滴管浓硝酸后迅速插入细口瓶中(如右图所示),滴管与瓶口接触处垫一小块滤纸使滴管与瓶口留少量空隙,依次观察到如下现象:①滴管内产生红棕色气体,液面下降;②滴管内液面上升,气体变成无色;③滴管内液面再次下降。下列不正确的是 (    )

A:现象①中产生的红棕色气体为NO2

B:产生现象②的原因是NO2与水反应

C:产生现象③的原因是铜与稀硝酸反应

D:最终瓶内溶液中的溶质只有Cu(NO3)2

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D

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    When I was seven years old, I got the greatest Christmas gift ever.____Now I realize I actually have the power to be a superhero. I may not able to fly, but I make a difference to someone's life. We all have the power to be a superhero to someone. Here are four ways you can be a real life superhero.

    ____Think about what it is. It could be your support, time, advice, a small gift or a thank-you card. Sometimes, even just the most harmless message can bring someone out of darkness and into the light. It's something that you have to give that can help others.

    Keep yourself healthy.____Look after your body and helping people will be easier. You'll have a clear mind and energy to achieve any task in your way.

    Pick your fight. Every superhero has a battle. It's something that drives them to be the person they are.____It could be anything such as working towards helping reduce the number of homeless people on the street. The fight does not need to be big, but it needs to be powerful.

    Make someone's day. Real life superheroes try to improve the lives of all the people they meet.____You can also try your best to absolutely make someone's day every once in a while. The people who get your help will thank you for it.

A. What's your fight?

B. Stay happy all the time.

C. It was a Batman costume, complete with bell and shoes.

D. Use the things you have to help someone without them.

E. You can't be a superhero if you don't take care of your body.

F. They try their best to turn someone's bad day into a good one.

G. They just want to get up, save the world and forget it ever happened.