下图反映单位体积空气所能容纳的最大水汽量与气温的关系。
一定体积空气中含有的水汽量与同温度下这些空气所能容纳的最大水汽量的比值称为相对湿度。测得一封闭实验箱内的温度为30℃，相对湿度是50%，如果要使实验箱内的相对湿度降低到37.5%，箱内温度应调节为（）。
A．35℃
B．25℃
C．15℃
D．5℃
参考答案：A
解析：
据图可知，气温为30℃时，最大水汽量为30g/m3，又知相对湿度为50%，那么此时空气中含有的实际水汽量为15g/m3。当相对湿度降低至37.5%时，可得出最大水汽量为40g/m3，此时气温为35℃。因此本题选A。
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| My wife was shouting at Sindu again. I threw the paper away and rushed to the scene. My daughter Sindu looked 1__. Her eyes were wet with tears. In front of her was a bowl 2_ with bitter melon. Sindu particularly hated bitter melon, but my wife believed_3_ in the "cooling effects" of bitter melon. I tried to _4_ Sindu to take a fewmouthfuls. She 5__ down a bit and wiped her tears. Then she said she would eat the _6_bowl of bitter melon on condition that I gave her whatever she asked for. I agreed. Slowly and _7_ , she finished the whole bowl. After that, Sindu came to me with her eyeswide with 8__. To our surprise, she wanted to have her head 9__. "Impossible!"shouted my wife. However, I knew that if I 10__ on my promise, Sindu would neverlearn to 11 her own. So I decided to keep my promise. On Monday morning, I 12__ her off at school. Just then,a boy shouted, "Sindu,wait for me!" What struck me was 13 hairless head. I was about to leave when a ladycame to me and said, "Sir, your _14_is great indeed!" I didn't _15_.She continued, "That boy is my son. He is 16__ from Leukemia (白血病). He lost all his hair_ 17__the side effects of the chemotherapy (化疗) He _18_ to come back to school because he was afraid that the kids at school would make fun of him. Sindu visited him last week andpromised to help him, but I 19__ imagined that she would sacrifice her lovely hair for thesake of my son! Sir, you and your wife are blessed to have such a(n) 20__ soul for a child. " I didn't know what to say. It was then that I knew what love really was. | ||||
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