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问题 单项选择题

胰腺病变腹痛时常向左背部带状放散，其原因是由于（）

A.胰腺位于腹后壁，是腹膜外器官

B.胰腺炎症，水肿压迫邻近器官及组织

C.胰腺病变可累及腹腔神经丛

D.胰液逆流胆管及胆囊，反射性疼痛

E.以上都不是

答案

参考答案：C

单项选择题 案例分析题

Transportation Decision Transportation decision consists of the following parts: 1.Selection of the mode is determined by the consideration of distance,cargo weights,linkage,timing and other requirements.Generally speaking,rail has high fixed cost and the relatively low variable cost.It can move heavy,large quantity of cargo in the long distance.But,rail is disadvantaged because of the longer transit time and less frequent service than motor. Motor carriers such as truck companies offer door-to-door service,that is,the cargo can be shipped from the shipper＇swarehouse to the consignee＇s.Trucking fixed cost is the lowest of any carrier,because the equipment is fairly cheap and the motor carriers do not have to invest in the roads on which they run their operations.However,their variable costs are very high.Its expenses include two major components:firstly,the pick-up and delivery costs;secondly,there are gas or fuel costs,labor expenses and toll roads fees to be paid to highway and toll road operators Therefore,motor transport is good for cargo with small quantity to be shipped within short distances. Water is the predominant choice of transportation as it has the capacity to take greatest quantity,travel longest distance with lowest cost.Transport by sea accounts for 80% of in-ternational trade.The major expenses for water are expenses associated with investment and maintenance of the ships and terminals.For example,a 100000-ton container ship costs US$ 200 million.Terminal associated costs include harbor fees and the cost for loading and unloading the goods. Transport by air has the highest cost but it is fast with the lowest ratio of loss and dam-age.If you need to deliver an urgent order,there is little choice but by air. 2.Transport service provider is selected for its experiences,equipment,services and prices.Competitive in the transport industry usually drives the prices down and motivates for better services.A company also chooses its transport service provider because of its long-standing business relationship with certain shipping companies. 3.The alternative routing and scheduling is specific for motor only because railway and water have strict route and timetable.Motor has special advantage in terms of flexibility.It has the ability to load goods at greater frequency,travel through different routes and making deliveries to different loca-tions.Questions:

Which mode account for most delivery in international trade？（）

A.By railway.

B.By water.

C.By air.

D.By trucks.
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选择题

下列方程中，解为x=4的是[ ]

A.3x+2=4x+5

B.x+3=2x+9

C.3+x=3x+2

D.4x-2=3
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