Many people travel to different places in the world by air. Usually it takes a long time, perhaps half a day, for passengers to stay in the plan. So airlines（航空公司）offer passengers food. But it is common that they feel bad about food taste. Do you agree?

    To solve this problem, airlines try hard to improve their food. They would like to do so because they don't want to lose customers.

    However, according to scientific research, part of the reason why plane food tastes bad is that at high altitude（海拔）we can not taste things as well as we do on the ground. Also scientists have found that our noses become very dry even before a plane takes off. As the plane moves up, the change in air  pressure（气压）reduces one third of the sensibility（感觉）of our taste buds（味蕾）. So our taste buds become senseless. The sad face, however, is that our noses don't know it.

    All of these help explain why food on the plane tastes so bad. They also help explain why airlines choose to offer passengers salty and spicy（辛辣的）food. Without doing so, the food would be tasteless.

    Now there are many researches on this. According to one of them, some volunteers are asked to lie with their feet higher than their heads for weeks. And scientists write down their feelings about food taste.

    Though scientists try their best, it is not as easy as they thought. Because they can't deal with the special environment successfully, such as the change in air pressure, making food taste good is still hard for them.

地处赤道附近的乞力马扎罗山山顶终年积雪，成为“赤道雪峰”，其主要原因是（   ）

填入下面文段空白处的词语，最恰当的一组是（    ）

    人们相信伪科学和谣言的另一个重要原因是人类个体的“偷懒”习惯﹣﹣我们在认如上的“吝啬”，会让我们通过捷径来处理信息。①     这种认知捷径会受到先入为主的信息左右，②     起初我们接受的信息存在着偏差，③    后续改变这种态度和观点的难度就会很大，④      我们会用已有的观点来同化后续的信息和观点。⑤    从这个角度来说，我们就要注重科学传播的质量﹣﹣这不仅包括科学性，⑥     要和公众的日常生活结合起来，让科学更接地气。

如图所示，开口向上的汽缸C静置于水平桌面上，用一横截面积S=50cm²的轻质活塞封闭了一定质量的理想气体，一轻绳一端系在活塞上，另一端跨过两个定滑轮连着一劲度系数k=2800N/m的竖直轻弹簧A，A下端系有一质量m=14kg的物块B．开始时，缸内气体的温度t₁=27℃，活塞到缸底的距离L₁=120cm，弹簧恰好处于原长状态．已知外界大气压强恒

为p₀=1.0×10⁵ Pa，取重力加速度g=10m/s²，不计一切摩擦．现使缸内气体缓慢冷却，求：