题干

如图所示,质量不计的活塞把一定质量的理想气体封闭在上端开口的直立圆筒形气缸中,活塞上堆放细砂,活塞处于静止状态.现在对气体缓慢加热,同时不断取走细砂,使活塞缓慢上升,直到细砂全部取走,则在此过程中(    )

A:气体压强增大,内能可能不变

B:气体温度可能不变,气体对外做功

C:气体的体积增大,压强减小,对外不做功

D:气体对外做功,内能一定增加

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B

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    They say if you love your job, you'll never work a day in your life. We say if you travel for work, you'll never have a boring commute(上下班往返) a day in your life. If the typical 9-to-5 isn't working for you, here are some options that will pay you to travel. No matter your current skill set, you can probably do it somewhere else.

Represent abroad

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    A cruise ship is a floating village. Therefore, any job that you could have in a village you could have onboard a ship-even auctioneering(做拍卖师). Carnival is hiring an art auctioneer to work aboard a luxury cruise ship. The only qualifications necessary are a college degree and public speaking skills. Going…going…sold.

Write the rails

    Writers can reimagine themselves as rail-surfing Jack Kerouacs, crossing the country and writing from coast to coast on the Amtrak Writer's Residency. The application process consists of two questions, as well as the opportunity to provide up to a 20-page writing sample. Amtrak will select 24 writers to participate in the program with the help from a panel of judges. Although the project won't replace a full-time job, it's really a fun opportunity. The application period for 2016 has closed, but applications will reopen in the fall.