如图所示为一定质量的海波熔化过程中，某同学描出的温度随时间变化的图象．下列根据图象做出的判断，正确的是（ ）
A．0至5min内海波的温度不断升高，说明海波的熔点不断升高
B．5min至10min内海波的温度不变，海波的内能不变
C．5min至10min内海波的温度不变，但海波在这段时间内仍然吸热
D．10min以后海波已全部变成气态，温度进一步升高
答案：C
解：A、从图象上看，0～5min内表示海波的温度逐渐升高，但不能它的熔点也在升高，故本选项说法错误．
B、5min至10min是海波的熔化过程，此时海波的温度不变，但是继续吸热，故其内能不断增大，故B错误；
C、5min至10min是海波的熔化过程，此时海波的温度不变，但是继续吸热，故C正确；
D、在10min以后海波已经全部熔化完毕，变成液态，温度进一步升高，故D错误．
故选C
| 完形填空。 Last Sunday Mr Clark and his wife went to the seaside. They arrived home very 1 . Mr Clark unlocked the front door and they all went into the house. It was very dark so Mrs Clark turned on the 2 . _ 3_ the way upstairs Mrs Clark spoke in a low voice, "Listen! I can 4 . someone in the living room. " They all went downstairs again and stood 5_ outside the living room door. They could hear voices in the living room. "You are 6 . " Mr Clark said, "There are two men there. They are talking. " Then he called out, "Who is there?" But _ 7 answered. Mr Clark 8 the door quickly and turned on the light. There wasn't anyone in the room. Then he noticed something and laughed. The radio was 9 on. "I remembered 10 this morning, " he said, but I forgot ! " | ||||
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