题干

下图1.2017年3月文物工作者在成都市青白江区大弯镇双元村发现了近200座春秋至战国时期的船棺墓群。出土上千件文物中,青铜器尤显异常精美,堪称一座“地下青铜器宝库”。与商周同期,我国西南地区已经盛行一种独特的青铜文化——“三星堆”文化。下列属于“三星堆”文化的青铜器是(    )

A:四羊方尊

B:司母戊鼎

C:青铜立人像

D:毛公鼎

上一题 下一题 0.0难度 选择题 更新时间:2016-02-25 03:05:42

答案(点此获取答案解析)

C

同类题5

阅读理解

    As the world's population grows, farmers will need to produce more and more food. And large farms are increasingly using precision farming to increase yields (产量), reduce waste, and reduce the economic and security risks that inevitably accompany agricultural uncertainty.

    Traditional farming relies on managing entire fields—making decisions related to planting, harvesting, irrigating, and applying pesticides and fertilizer (农药和化肥)—based on regional conditions and historical data. Precision farming, by contrast, combines sensors, robots, GPS, mapping tools and data-analytics software to customize(量身定制)the care that plants receive without increasing labor. Robot-mounted sensors and camera-equipped drones (无人机) wirelessly send images and data on individual plants to a computer, which looks for signs of health and stress. Farmers receive the feedback in real time and then deliver water, pesticide or fertilizer in adjusted doses(剂量)to only the areas that need it. The technology can also help farmers decide when to plant and harvest crops.

    As a result, precision farming can improve time management, reduce water and chemical use, and produce healthier crops and higher yields—all of which benefit farmers' bottom lines and conserve resources while reducing chemical runoff.

    Many small businesses are developing new software, sensors, and other tools for precision farming, as are large companies such as Monsanto, John Deere, Bayer, Dow and DuPont. The U.S. Department of Agriculture, NASA and the National Oceanic and Atmospheric Administration all support precision farming, and many colleges now offer course work on the topic.

    In a related development, seed producers are applying technology to improve plant characteristics. By following individual plants over time and analyzing which ones flourish in different conditions, companies can relate the plants' response to their environments with their genomics (基因组学). That information, in turn, allows the companies to produce seed varieties that will grow well in specific soil and weather conditions. This advanced technology may also help to improve crop nutrition.

    Farmers do not universally welcome precision agriculture for various reasons, such as high equipment costs and lack of access to the Internet. The technology may bring great challenges to experienced farmers who are not good at computers. And large systems will also be beyond the reach of many small farming operations in developing nations. But less expensive, simpler systems could potentially be applied. For others, though, cost savings in the long run may reduce the financial concerns. And however reticent some farmers may be to adopt new technology, the next generation of farmers are likely to warm to the approach.