题干

如图所示,有一种望远镜由两组凸透镜组成.靠近眼睛的叫目镜,靠近被观测物体的叫物镜.物镜的作用是使远处的物体在焦点附近成缩小的实像,这类似于(  )

A:照相机   

B:投影仪   

C:放大镜

D:幻灯机

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答案(点此获取答案解析)

A

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阅读理解

    On one evening 30 years from now, you might sit down to a table and get ready to have your dinner. What will you be eating? Will the food still be the same as it is now? Here are a few possible choices for the future.

Insects

    Insects take up little space and don't make much waste. They also have more protein than beef, chicken and pork. This makes insects another possible food of the future. Most people probably won't want to see the insects they eat. So in the future, people will first turn insects into powder to make with other foods like chips and biscuits.

Vegetable meat

    A new kind of burger(汉堡包)is now popular in the United States. It looks and tastes the same as any other burgers. But it's actually a "beef" burger made out of plants. People use peas and potatoes to make the "beef". They take coloring, protein and fats from these plants and mix them together.

Algae(藻类)

    It is said that algae farming could become the world's biggest farming in the future. Algae is cheap and grows, very quickly. Also, it is very good for people. It has much more protein and oil than many other plants. People may also use algae oil and algae butter in the future. Some algae has a strong taste.

Manmade meat

    Meat grown in labs might be another kind of future food. People use stem cells(干细胞) from animals to grow the meat. Chicken, beef, and pork can all be made this way. Manmade meat can be healthier than traditional meat. People can control what type of fat goes into the meat. They can choose only healthy fats.