题干

在生命科学发展过程中,证明DNA是遗传物质的实验是:(  )
①孟德尔的豌豆杂交实验
②摩尔根的果蝇杂交实验
③肺炎双球菌转化实验
④T2噬菌体侵染大肠杆菌实验
⑤ DNA的X光衍射实验

A:①②

B:②③

C:③④

D:④⑤

上一题 下一题 0.0难度 选择题 更新时间:2016-03-09 06:48:00

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C

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Exploit your parking space

    An unused parking space or garage can make money. If you live near a city center or an airport, you could make anything up to£200 or£300 a week. Put an advertisement for free on Letpark or Atmyhousepark

Rent a room

    Spare room? Not only will a lodger(房客)earn you an income, but also, thank to the government-backed "rent a room" program, you won't have to pay any tax on the first£4500 you make per year. Try advertising your room on Roomspare or Roommateeasy.

Make money during special events

    Don't want a full-time lodger? Then rent on a short-term basis. If you live in the capital, renting a room out during the Olympics or other big events could bring in money. Grashpadder can advertise your space.

Live on set

    Renting your home out as a "film set" could earn you hundreds of pounds a day, depending on the film production company and how long your home is needed. A quick search on the Internet will bring up dozens of online companies that allow you to register your home for free—but you will be charged if your home gets picked.

Use your roof

    You need the right kind of roof, but some energy companies pay the cost of fixing solar equipment (around£14,000),and let you use the energy produced for nothing. In return, they get paid for unused energy fed back into the National Grid. However, you have to sign a 25-year agreement with the supplier, which could prevent you from changing the roof.

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