题干

在两块相同的玻璃片上,小明同学分别滴一滴质量相同的水,如图所示.观察图中情景可知,他主要研究蒸发快慢是否与(  )

A:水的温度有关

B:水的表面积有关

C:水上方空气的流速有关

D:水的质量有关

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B

同类题1

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    The spring season brings warm weather, flowers and other changes for people to enjoy. For some restaurant cooks, the most exciting spring arrival is ramps.

    Ramps are a wild plant in the eastern mountains of North America. They are one of the first plants that grow in the spring, usually between April and May. They are recognized(意识) by their red stem(茎), and two long and wide green leaves. They are also famous for their strong taste, similar to onions(洋葱).

    Ramps are not as well-known as other vegetables, but they have a long history in the United States. In the Appalachian Mountains, ramps have been an important food for a longtime. During spring, it is common for small towns in the Appalachian area to hold large ramp dinners for the community.

    However, over the last 30 years, ramps popularity has grown quickly. They are now a highly-desired vegetable for many nice restaurants in cities like New York and Washington D.C.

    One reason the plant is popular is that it grows in the wild. It is difficult to grow them on farms. Most restaurants get them from foragers, who collect ramps by searching forests for some small pieces of land where they grow. Ramps have a short season. Within a few weeks of full growth, the plant is done for the year. This shot life is some reason for their popularity.

    And that popularity could lead Io their disappearance from Earth. In 1995, the local government in Quebee, Canada, stopped people selling the plant to businesses in order to protect the plant against being over-dug.

    The season is short, but it has not ended yet. If you are in the right place, you still have time to try a taste of ramps yourself.

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