问题
选择题
| 关于透镜，下列说法中正确的是（ ） A．凸透镜和凹透镜都有焦点，凸透镜有实焦点，凹透镜有虚焦点 B．凸透镜对光有会聚作用，因此通过凸透镜的光都一定会聚在焦点 C．凸透镜只对平行光有会聚作用 D．凹透镜只对平行光有发散作用 |
答案
答案：A
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| 关于透镜，下列说法中正确的是（ ） A．凸透镜和凹透镜都有焦点，凸透镜有实焦点，凹透镜有虚焦点 B．凸透镜对光有会聚作用，因此通过凸透镜的光都一定会聚在焦点 C．凸透镜只对平行光有会聚作用 D．凹透镜只对平行光有发散作用 |
答案：A
For years I wanted a flower garden. I would spend hours thinking of the different things I could that would look nice together. But then I had five lovely children: Matthew and Marvin, the twins Alisa and Alan, and then Helen. I was too raising them to grow a garden. Money was tight (紧的) ，as well as time. When my children were little, if they wanted something that too much I’d have to say, “Do you see a money outside? Money doesn’t grow on trees, you know.” Finally, all five got through high school and college, and started living on their own. And I started thinking again about having a . One spring morning, on Mother’s Day, I the window and was surprised to see a new tree in my yard. I put my glasses on and I couldn’t believe what I was looking at. There was a money tree in my yard! I went outside to look. It was true! There was as much as one hundred on that tree. All I could think of was all the garden flowers I could with that money! There was also a(an) attached(附上): “ Love, Marvin.” My other had bought me tools, ornaments(装饰物) and gardening books. That was three years ago. My garden is now very , just the way I wanted. I’m still not sure whether money on trees. But I know love does!
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