问题
选择题
用显微镜观察标本时，若所用的目镜是10X，物镜是15X，则被观察的物体放大了( )
A．5倍
B．150倍
C．15倍
D．50倍
答案
Ｂ
题目分析: 一台显微镜的目镜与物镜放大倍数的乘积就是放大镜的放大倍数，所以这台显微镜的放大倍数为１５×１０＝１５０倍
考点: 显微镜的使用。
搜题请搜索小程序“爱下问搜题”
用显微镜观察标本时，若所用的目镜是10X，物镜是15X，则被观察的物体放大了( )
A．5倍
B．150倍
C．15倍
D．50倍
Ｂ
题目分析: 一台显微镜的目镜与物镜放大倍数的乘积就是放大镜的放大倍数，所以这台显微镜的放大倍数为１５×１０＝１５０倍
考点: 显微镜的使用。
I was reading a notice at the entrance to my college dormitory, when a girl came up to me and said, “Do you _26_ a quarter? I’m one short of putting my laundry(刚洗好的衣物) in the dryer(烘干机). ” I _27_ to think about it for a few seconds and considered whether I’d be _28_ to give a quarter away. I found myself _29_ her, thinking about why she didn’t _30_ four quarters down from her room with her, as if she had _31_ to be one short so she could ask someone else for it. (Later I knew _32_ that was not the case.) But I didn’t have any reason to _33_her. Then I responded, “Yeah, I think I have the only one,” though fully _34_ that I had three. “Here you go,” I said with a smile. “Thanks,” she responded, _35_ that she could have clean clothes to wear the next morning. A few moments later the girl _36_ and gave a dollar bill to me. “Why are you giving this to me?” I asked, _37_. “Oh, because you were kind to me, so I’m just giving back the _38_.” It’s just a dollar, but I felt it was _39_. More so because I hadn’t given that quarter with such nice _40_, the way she gave that dollar to me. I felt like it was the first time I ever _41_ something greater in return for something so_42_ that I had given. I saw the power of kindness and generosity in a _43_way. I thought it was so worth giving that quarter away. Giving and _44_ don’t usually happen hand-in-hand, _45_ when it does, like it did this time, it makes one think about why generosity is so powerful in the first place.
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