题干

如图是一个由5张纸片拼成的平行四边形,相邻纸片之间互不重叠也无缝隙,其中两张等腰直角三角形纸片的面积都为S1,另两张直角三角形纸片的面积都为S2,中间一张正方形纸片的面积为S3,则这个平行四边形的面积一定可以表示为(   )

A:4S1

B:4S2

C:4S2+S3

D:3S1+4S3

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答案(点此获取答案解析)

A

同类题1

用括号里所给动词的适当形式填空。

    I recently heard a story about a famous scientist. Because of his great achievements, he was thought to be more creative than the ordinary person. When he ____ (ask) why he was able to do this, he gave the answer. It all came from an experience with his mother when he was about two years old. “I tried to get a bottle of milk from the fridge when I lost the bottle and it fell, spilling(溢出)the milk all over the floor — a sea of milk! I was frightened and I didn’t know what to do!” he said.

    His mother heard the noise and got into the kitchen. “I ____ (consider)how to explain all this to you, mom.” He said. Instead of ____ (punish) him, she said, “Robert, what a great mess(杂乱) you have made! I ____ (not see) such a huge sea of milk before! Well. since the milk has already been spilled, would you like to play in the milk for a while? We ____ (clean) it up after that.” Indeed, he did so. After a few minutes, his mother said, “You know, Robert, whenever you make a mess like this, finally you have to clean it up.” He used a sponge(海绵) and together they cleaned up the spilled milk. His mother then said, “You know, you ____(fail)in how to successfully carry a big milk bottle with two tiny hands just now. Let’s go out in the yard and fill the bottle with water to see if you can find a way to carry it.” Then the little boy learned that if he grasped (抓紧) the bottle at the top near the lip with both hands, he could carry it without dropping it. What a wonderful lesson!