在常温下不溶于任何溶剂，低温性能、抗冲击性和耐久性均比聚氯乙烯管好的塑料管是（）。

通常认为，抛掷一枚质量均匀的硬币的结果是随机的。但实际上，抛掷结果是由抛掷硬币的冲力和初始高度共同决定的。尽管如此，对抛掷硬币的结果作出准确预测还是十分困难。下面哪一项最有助于解释题干所说到的现象，即抛掷结果被某些因素决定，但预测却很困难

A．很长时间以来，抛掷硬币已被用作随机事件的典型例证。

B．如果抛掷一枚质量不均匀的硬币，其结果总能够被精确地预测。

C．如果抛掷硬币的初始高度保持稳定不变，则抛掷硬币的结果将仅由抛掷冲力决定。

D．对抛掷硬币结果的准确预测，要求极其精确地估计抛掷硬币的初始高度和冲力。

针灸治疗漏肩风的经验穴是（）。

A.后溪

B.悬钟

C.条口

D.外劳宫

E.大杼

料民于太原

阑尾切除术后半年，突然阵发性腹痛，呕吐粪样物，排便排气停止三天。检查：腹膨隆，可见肠型，散在压痛，肠鸣音亢进，可闻气过水声，腹部X线透视见阶梯状气液平，首先应考虑（）

A.急性胃肠炎

B.粘连性肠梗阻

C.肠扭转

D.肠套叠

"What does the middleman do but add to the price of goods in the shops " Such remarks are aimed at the intermediate operations between manufacturers and final customers. This practice usually attracts a lot of attention from the public and the press and the operation most talked about is what is often called wholesaling.The wholesaler buys goods in large quantities from the manufacturers and sells them in smaller parcels to retailers, and for this service his selling price to the retailer is raised several percent higher. But his job is made more difficult by retail demand not necessarily running level with manufacturers’’ production. Because he adjusts or regulates the flow of goods by holding stock until required, he frees the manufacturer, to some extent, from the effect on production of changing demand and having to bear the whole risk.The manufacturer can then keep up a steady production flow, and the retailer has no need to hold heavy stocks, who can call on the wholesaler for supplies any time. This wholesale function is like that of a valve in a water pipe. The middleman also bears part of the risk that would otherwise fall on the manufacturer and also the retailer.The wholesaler provides a purely commercial service, for which he is too well rewarded. But the point that is missed by many people is that the wholesaler is not just someone adding to the cost of goods. It is true one could eliminate the wholesaler but one would still be left with his function: that of making sure that goods find their way to the people who want them.

The wholesaler regulates the flow of goods by________.

A．running level with manufacturers’ production

B．holding down stock of commodities

C．keeping stock for per demand

D．adjusting the prices of goods in time