题干

已知反应:2NO2 (红棕色)⇌N2O4(无色)△H<0.将一定量的NO2充入注射器中后封口,如图是在拉伸和压缩注射器的过程中气体透光率随时间的变化(气体颜色越深,透光率越小).下列说法正确的是(   )

A:b点的操作是压缩注射器,平衡正向移动

B:c点与a点相比,c(NO2)增大,c(N2O4)减小

C:d 点:v(正)>v(逆)

D:若不忽略体系温度变化,且没有能量损失,则T(b)>T(c)

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A

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    Fresh off his MasterChef Junior run, Evan Robinson, who is only 12 years old, is using his kitchen skills to raise money for Puerto Rico. The TV show contestant wanted to offer help after hurricanes(飓风) hit the country last September.

    “I've been seeing, all over the news, people struggling,” Evan said. “They can't get fresh water, electricity; they can't get really anything. I know I'm just a kid, but I think if a lot of people do something, a lot of things will get better.”

    He raises money by baking and taking online orders for homemade empanadas(馅 饼). He started cooking on a recent Friday night. By the next Sunday evening, he had filled orders for 420 empanadas — — roasted chicken, cheeseburger and vegetarian — — getting $18 for six empanadas and $30 for a dozen.

    His mom, Veronica Robinson, helped him send the empanadas around the city. “We've never done anything like this before,” she said. “But it's a great idea, so I want to help him make it work.”

    For Evan's out-of-town friends and supporters, he has set up a crowdfunding(众筹) page. Through it, he's hoping to raise $1, 500 in “virtual (虚 拟 的) empanadas”. This is because he heard on the news that it could take Puerto Rico years, maybe  even 10 years, to recover(复 原) from the hurricanes. And he said, “Fruit pies are up next. And my baking will continue as well.”

    It's a difficult job, especially for a kid with homework and Boy Scouts and friendships to tend to. But he doesn't seem worried.

    “It's what we're supposed to do.” he said. “I'm a human. They're humans. Why shouldn't I help them?”

    Indeed.