某电子商务公司要从A地向B地的用户发送一批价值90000元的货物。从A地到B地有水、陆两条路线。走陆路时比较安全，其运输成本为10000元：走水路时一般情况下的运输成本只要7000元，不过一旦遇到暴风雨天气，则会造成相当于这批货物总价值10%的损失。根据历年情况，这期间出现暴风雨天气的概率为1/4，那么该电子商务公司(70)。
D.可以随机选择路线

多项选择题有关对城市桥梁工程模板支架搭设及拆除的安全措施的说法中，正确的是( )。

单项选择题A、 B、 C、 D、

未分类题The climate of Earth is changing. Climatologists are confident that over the past century, the global average surface temperature has increased by about half a degree Celsius. This warming is thought to be at least partly the result of human activities, such as the burning of fossil fuels and the clearing of forests for agriculturE.As the global population grows and national economies expand, the global average temperature is expected to continue increasing by an additional 1.0℃ to 3.5℃ by the year 2100.Climate change is one of the most important environmental issues facing humankinD.Understanding the potential impacts of climate change for natural ecosystems is essential if we are going to manage our environment to minimize the negative consequences of climate change and maximize the opportunities that it may offer. Because natural ecosystems are complex, nonlinear systems, it follows that their responses to climate change are likely to be complex. Climate change may affect natural ecosystems in a variety of ways. In the short term, climate change can alter the mix of plant species in land ecosystems such as grasslands. In the long term, climate change has the potential to dramatically alter the geographic distribution of major vegetation types—savannas, forests, and climate change can also potentially alter global ecosystem processes, including the cycling of carbon, nitrogen, phosphorus, and sulfur. Moreover, changes in these ecosystem processes can affect and be affected by changes in the plant species of the ecosystem and vegetation typE.All of the climate change—induced alterations of natural ecosystems affect the services that these ecosystems provide to humans.The global average surface temperature increase of half a degreE.Celsius observed over the past century has been in part due to differential changes in daily maximum and minimum temperatures, resulting in a narrowing of the diurnal temperature rangE.Decreases in the diurnal temperature range were first identified in the United States, where large-area trends showed that maximum temperatures have remained constant or increased only slightly, whereas minimum temperatures have increased at a faster ratE.In this issue, Alward et al report on the different sensitivities of rangeland plants to minimum temperatures increases.Which of the following is NOT mentioned as a reason for the global warming?A.The burning of fuels such as coal or oil.B.The clearing of forests.C.The cultivation of farmlanD.D.The negative consequences of human activities.

单项选择题如图，试求ab间的等效电阻。

未分类题Bill: Hello, KatE.Kate: Hello, Bill,______. Bill: I'm going to do some shopping in the town. Kate: I'm going to catch a train. I'm waiting for a bus.A.What's the matter with you?B.Good-byE.C.Nice to have seen you herE.D.Nice to see you herE.

未分类题After World War II the glorification of an ever-larger GNP formed the basis of a new materialism, which became a sacred obligation for all Japanese governments, businesses and trade unions. Anyone who mentioned the undesirable by-products of rapid economic growth was treated as a heretiC.Consequently, everything possible was done to make conditions easy for the manufacturers. Few dared question the wisdom of discharging untreated waste into the nearest water body or untreated smoke into the atmospherE.This silence was maintained by union leaders as well as by most of the country's radicals; except for a few isolated voices, no one protesteD.An insistence on treatment of the various effluents would have necessitated expenditures on treatment equipment that in turn would have given rise to higher operating costs. Obviously, this would have meant higher prices for Japanese goods, and ultimately fewer sales and lower industrial growth and GNP.The pursuit of nothing but economic growth is illustrated by the response of the Japanese government to the American educational mission that visited Japan in 1947. After surveying Japan's educational program, the Americans suggested that the Japanese fill in their curriculum gap by creating departments in chemical and sanitary engineering. Immediately, chemical engineering departments were established in all the country's universities and technical institutions. In contrast, the recommendation to form. sanitary engineering departments was more or less ignored, because they could bring no profit. By 1960, only two second-rate universities, Kyoto and Hokkaido, were interested enough to open such departments.The reluctance to divert funds from production to conservation is explanation enough for a certain degree of pollution, but the situation was made worse by the type of technology the Japanese chose to adopt for their industrial expansion. For the most part, they simply copied American industrial methods. This meant that methods originally designed for use in a country that stretched from the Atlantic to the Pacific with lots of air and water to use as sewage receptacles were adopted for an area a fraction of the sizE.Moreover, the Japanese diet was much more dependent on water as a source of fish and as an input in the irrigation of rice; consequently discharged wastes built up much more rapidly in the food chain.Notes:heretic 异教徒sanitary 卫生的for the most part 基本上receptacle 储存地According to the text, no measures were resorted to in environmental protection after World War Ⅱ in Japan becauseA.they were reckoned to be unnecessary.B.they would check economic development.C.no one was much interested in them.D.pollution was held as inevitable at that timE.

单项选择题强某带女儿（6岁）随父亲乘飞机去南方滨海城市度假，不料飞机事失事，飞机上的人全部死亡。经查，强某的妻子于女儿出生时死亡，强某有四个亲兄弟姐妹。对在这场意外事故中死亡的强某及女儿与父亲可以推定他们同时死亡。（）

未分类题多媒体版本的“清明上河图”分成54个场景进行高分辨率扫描，每个场景约为58．3MB，那么全图所需的存储容量是A.1．15GBB.2．15GBC.3．15GBD.4．15GB

未分类题如果网络节点传输1字节数据需要1X 10-9s，则该网络的数据传输速率为D.8Gbps

单项选择题Which of the following has themost notable variation in the skeletal system