题干

对下列四幅图阐述正确的是(  )

A:近视眼成像在视网膜前,用凸透镜矫正

B:远视眼成像在视网膜后,用凹透镜矫正

C:显微镜的目镜相当于放大镜,物镜相当于摄像机的镜头

D:天文望远镜的目镜相当于放大镜,物镜相当于照相机的镜头

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D

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    Failure is probably the most exhausting experience a person ever has. There is nothing more tiring than not succeeding.

    We experience this tiredness in two ways: as start-up fatigue (疲惫) and performance fatigue. In the former case, we keep putting off a task because it has either too boring or too difficult. And the longer we delay it, the more tired we feel.

    Such start-up fatigue is very real, even if not actually physical, not something in our muscles and bones. The solution is obvious though perhaps not easy to apply: always handle the most difficult job first.

    Years ago, I was asked to write 102 essays on the great ideas of some famous authors. Applying my own rule, I determined to write them in alphabetical order, never letting myself leave out a tough idea. And I always started the day's work with the difficult task of essay-writing. Experience proved that the rule works.

    Performance fatigue is more difficult to handle. Though willing to get started, we cannot seem to do the job right. Its difficulties appear so great that, however hard we work, we fail again and again. In such a situation, I work as hard as I can—then let the unconscious take over.

    When planning Encyclopedia Britannica( 《大英百科全书》), I had to create a table of contents based on the topics of its articles. Nothing like this had ever been done before, and day after day I kept coming up with solutions, but none of them worked. My fatigue became almost unbearable.

    One day, mentally exhausted, I wrote down all the reasons why this problem could not be solved. I tried to convince myself that the trouble was with the problem itself, not with me. Relived, I sat back in an easy chair and fell asleep.

    An hour later, I woke up suddenly with the solution clearly in mind. In the weeks that followed, the solution which had come up in my unconscious mind proved correct at every step. Though I worked as hard as before, I felt no fatigue. Success was now as exciting as failure had been depressing.

Human beings, I believe, must try to succeed. Success, then, means never feeling tired.