题干

某实验小组同学为了探究铜与浓硫酸的反应,进行了如下实验,实验装置如图所示.

实验步骤:

①先连接如图所示的装置,检查好气密性,再加入试剂;

②加热A试管,待B试管中品红溶液退色后,熄灭酒精灯;

③将Cu丝向上抽动离开液面.

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    I'm a 20-year-old boy,and the following is my story.

    A month after I graduated from high school in August,2007,I was coming home from swim practice in the training centre of the city and was involved in a car accident.I was so seriously injured that I was in a coma for more than two months at Prince Georges Hospital.

    I suffered a lot from the experience of dying eight times during my coma and I couldn't open my mouth to talk or to communicate when I eventually came around.At that time,it seemed that walking was never going to happen again due to all the extreme injuries.Just like my body,my dreams were completely destroyed.But I was not going to let my injuries stop me from realizing my dreams.

    After receiving a total of 15 operations and 36 blood transfusions,I had to make every great effort to learn to talk,eat,walk,shower,and live on my own again.When I was out of hospital,I still had to Go to outpatient therapy in Waldorf,Maryland.After I spent a few months in a wheelchair,I took baby steps to walk on my own.It was a miracle that I was able to walk again,but I still wanted to prove that I could not only walk,but also run.When it came true,I wanted to get back into the pool again.After having a few lung tests,I was able to go in the pool a little bit each week. After a few months of swim training,I began my freshman year at St.Mary's College of Maryland and then became a proud member of the swim team.

    By telling my story,I want to make a positive influence on the world.I am just trying to live every day to the fullest and inspire other people never to give up their dreams no matter how bad a situation is to them.I remember when I was still in my hospital bed,I would have my mom and dad push me round in my wheelchair to the other rooms to see the other patients and chat with them and their family members.I wanted to let them know that everything was going to be okay.Somehow,things would work out for the best.