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问题 单项选择题 B1型题

药材中的水和脂肪等能不同程度地吸收微波能量，并把它转变为热量的干燥方法是（）

A.远红外加热干燥养护技术

B.微波干燥养护技术

C.无公害气调养护技术

D.除氧剂封存养护技术

E.辐射防霉除虫养护技术

答案

参考答案：B

实验题

玮琦同学想探究“小灯的亮暗程度与什么因素有关”，于是找来额定电流均小于0.6 A，额定电压分别是2.5V和3.8V的灯L1和灯L2，先后接在电源电压恒为6V的电路中，按照如图所示的电路开始探究。

（1）请你用笔画线代替导线，根据图所示的电路图，向左移动滑动变阻器滑片会使灯变亮，相应地将图所示实物图连接完整。

（2）若玮琦同学连接完电路,将滑动变阻器调到最大值后，闭合开关，发现电压表指针反向偏转，则原因是她将电压表负接线柱可能与     （选填“A”、“B”、“C”、“D”或“E”）接线柱误接。

（3）她按照电路图纠正接线后，继续进行实验：

①闭合开关，移动滑片P，使灯L1发光，测出灯L1的相关物理量，记录和计算结果如下表：

次数电压／V 实际功率／W电阻Ω
11.6O.20O.328.00
22.5O.24O.601O.42
32.8O.26O.731O.77
②请你将她记录数据时遗漏的物理量和单位填入表格的空格处。

（4）实验发现：灯L1的亮度，第二次比第一次亮，第三次比第二次更亮。结合表中数据得出的结论是小灯泡越亮，它的实际功率越          。

（5）用L2替换L1重复上面的实验时，需要改变          表的量程，发现灯L2的亮度变化规律与灯L1相似。

（6）实验结束后，,她与同学们还进行了讨论和交流：

①梦依同学认为“将上表中灯L1的3次电阻求平均值，可作为灯L1正常发光时的电阻”。大家对这种说法进行了否认，原因是她忽视了             会影响小灯的电阻。

②占鑫同学认为把灯L1换成定值电阻，该实验可以用来“探究导体中的电流与电压的关系”。大家对这种说法进行了          （选填“肯定”或“否定”）。
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问答题

In these times when market forces appear increasingly complicated and more volatile, it is all the more important to understand the professional jargon and terminology in the market place in order to be able to better make our investment and business decisions. Understanding key economic indicators will assist in the decision making process, providing a snapshot of the current situation and an insight into the future.
(46) Each economic indicator tells us something about the economy or inflation. Gross Domestic Product (GDP) is probably the most important report as it is the whole framework where other economic indicators fall under.
There are also indicators that are broader tell us about the economy itself rather than the components, e. g. employment figures, leading indicators, money supply figures (M3). Inflation figures, Produce Price Index (PPI) and the Consumer Price Index (CPI) will, in short, inform us of the changes in wholesale prices, cost of consumer (retail) goods and services respectively.
An indicator that is useful must be accurate, timely and reliable. It depends entirely on the integrity of the national statistical system responsible. It is vital to know the accurate components of an indicator. We have to be mindful of the limitation of these statistical figures too.
Some indicators can be historic or extremely volatile, and therefore their values are reduced. It is better to compare the most recent data with earlier months, or take a moving average for the past 3, 6 or 12 months to smooth the data. It will tell us if there has been a significant change in trend and whether a new direction is under way.
Timeliness of an indicator is also significant. (47) Although the reported figures are important, it is crucial to recognize that markets react more to the variance to the consensus forecast than to the absolute change in the indicator. (48) Markets do not like surprises and can be frustrated with volatility upon subsequent revisions to the numbers published, even though significance of the absolute number diminishes with each passing month.
The Index of Leading Economic Indicators (L. E. I) in the US acts as an early warning system, telling us when the economy is about to change direction. (49) This composite index of 11 leading indicators has a good record of providing accurate forecasts. The total index performs better as a prediction tool than any of its parts. This monthly figure is available on the last business day of the month and has low volatility.
(50) As a general rule, turning points in the economy are signaled by three consecutive months of L. E. I changes in the same direction. This leading indicator is like a lighthouse, giving the rest of the world economies a glimpse of the direction of the’ world’s largest economy.
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