题干

下面是光学显微镜示意图,对光时,转动____,使低倍物镜正对通光孔;然后,将遮光器的一个合适的光圈对准通光孔;注视目镜,并转动____使视野明亮。

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答案(点此获取答案解析)

⑤,⑦

同类题3

下表中不能体现19世纪后半期铁路交通发展的基本特征的是(     )
1870—1900年的铁路网         单位:千公里
年份
全世界
欧洲
美洲
亚洲
非洲
澳洲
1870年
1880年
1890年
1900年
210
372
617
760
105
169
224
284
93
175
331
402
8
16
34
60
2
5
9
20
2
8
19
24

同类题5

阅读理解

    A psychologist walked around a room while teaching stress management to the audience. As she raised a glass of water, everyone expected they'd be asked the “half empty or half full” question. Instead, with a smile on her face, she inquired. “How heavy is this glass of water?”

    Different answers are called out from the audience.

    She replied, “The absolute weight doesn't matter. It depends on how long I hold it. If I hold it for a minute, it's not a problem. If I hold it for an hour, I'll have an ache in my arm. If I hold it for a day, my arm will feel numb and paralyzed. In each case, the weight of the glass doesn't change, but the longer I hold it, the heavier it becomes.”

    She continued. “The stresses and worries in life are like that glass of water. Think about them for a while and nothing happen. Think about them a bit longer and they begin to hurt you. And if you think about them all day long, you will feel paralyzed and be incapable(无能力的)of doing anything.”

    It's important to remember to let go of your stresses. As early in the evening as you can, put all your burdens down. Don't carry them through the evening and into the night.

    Remember to put the glass down!”

    Comments:

    Aye Chan Aung-February 27, 2017 at 11:37am

    Short but valuable! It clearly teaches me how to deal with stresses.

    Nelson Malicdem-February 28, 2017 at 8:23 pm

    Wow! Thank the author and the one who submitted the article. I am experiencing a challenge when I read this. It gives me peace. What exactly is in the article is what I am doing. My burden actually paralyzes me without my knowing it. I put down the glass of water that I am holding. Thank you so much!