一齿轮箱在温度T=370K的稳定状态下工作，周围环境为270K。每分钟_爱下问搜题

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问题单项选择题

一齿轮箱在温度T=370K的稳定状态下工作，周围环境为270K。每分钟内齿轮箱中传向环境的热Q为300kJ。现取齿轮箱及其环境为一孤立系统，每分钟内系统的熵增为( )kJ/K。

A．0～0.1
B．0.1～0.2
C．0.2～0.4
D．0.4～0.6

答案

参考答案：C

单项选择题

睾丸及附睾的急性化脓性感染称为

A．子痰

B．囊痈

C．子痈

D．脱囊

E．卵子瘟

完形填空

Coin confusion
Rachel looked through troubled eyes at her sister and said, "I wouldn't have thought Eric would be a thief." Her sister Sarah replied, "Whoa, that's a      accusation to make against your best friend!"
Rachel remembered two days ago when she had brought out her coin collection for Eric to     . At the end of that day, Rachel's mother asked her to do her a favor, so she asked her friend," Is it okay if I leave you for a few minutes?" Eric said, "Go ahead. I’ll clean up here,"      at the piles of coins on the floor.
When Rachel returned, it never occurred to her to     her coins until two days later that she realized some quarters were      .
Sarah said, "Why don't you just ask him?"
"Ask him what? Hey, best friend, did you       my coin collection?" Rachel thought for a moment,        if that would be a good idea. The theft of her collection left her with a feeling of        "How could I have misjudged my friend's       ?"
The next day Rachel went to Eric's house. Eric was acting funny sort of nervous, like he couldn't be       . In fact, Rachel thought Eric acted like someone with a secret. Anger blossomed as Rachel watched Eric pretend to be kind,      Eric had obviously stolen from her. Rachel finally could not stand it anymore and stood up. Suddenly, Eric     ,"I can't stand it anymore!" Rachel was astonished at hearing her own      burst forth from her friend! Instead of sounding     , Eric sounded excited. He pulled something from underneath the chair.
"Go to open it! I was going to wait until your birthday, but I can't wait." Slowly, Rachel lifted the top of the     . Laid out in front of her were all of the quarters from her coin collection. Each quarter was in its own      in a new collection case. Each quarter shone like it was new.
Rachel felt      rush over her neck and ears. She said     , "Thank you! This means... a great deal to me." She was grateful that Eric had cut her      before she said something she would     . Eric was exactly the type of person she wanted as a friend!

B．unwillingly