题干

如图所示,劲度系数为k2的轻弹簧乙竖直固定在桌面上,上端连一质量为m的物块;另一劲度系数为k1的轻弹簧甲固定在物块上.现将弹簧甲的上端A缓慢向上提,当提到乙弹簧的弹力大小恰好等于
2
3
mg时,求A点上提的高度.

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    I had an experience once which taught me something about the ways people made a bad situation worse by blaming themselves. One January, I officiated (主持) at two funerals for two elderly women.____At the first home, the son of the deceased (已故) woman said, “If only I had sent my mother to Florida and gotten her out of this cold and snow, she would be alive today. It's my fault that she died.” At the second home, the son said, “If only I had not insisted her going to Florida, she would be alive today.____ It is my fault.”

    When things don't turn out as we would like them to, we tend to assume that had we done things differently, the story would have had a happier ending. Any time there is a death, the survivors will feel guilty. Because the course of action they took turned out bad, they believe that the opposite course, for example, keeping mother at home, would have turned out better.____

    There seem to be two elements involved in our readiness to feel guilty. The first lies in our belief that the world makes sense—there is a reason for everything that happens.

    The second is the thought that we are the cause of what happens, especially the bad things that happen.____A baby comes to think that the world exists to meet his needs, and that he makes everything happen in it. He wakes up in the morning and calls the rest of the world to its tasks.____When he is hungry, people feed him, and when he is wet, people change him. Very often, we do not completely abandon that childish thought that our wishes cause things to happen.

A. That long airplane ride was more than she could take.

B. After all, how could it have turned out any worse?

C. Life and dead is an unsolved mystery.

D. The roots of this feeling may lie in our childhood.

E. He cries, and someone comes to attend to him.

F. Both died a natural death.

G. They believe that they are responsible for what has happened.