题目

在“伏安法测电阻”的实验中，某同学在操作时不小心将电流表与电压表的位置接反了，则[    ]A．电流表被烧坏B．电压表被烧坏C．电流表示数为零D．电压表示数约为电源电压 答案：CD解析:p;【解析】略 阅读理解 　　The Tang Dynasty was probably the period when the Silk Road was at its busiest．One important center on the road was the city of Chang’an, where present-day Xi’an now stands．Chang’an was the capital city of this dynasty and by about 750 AD it had become a strong and successful capital of around two million people．Because of the chances for trade, a number of foreigners from countries bordering China lived in the city． 　　The markets at this time in Chang’an were perhaps the most exciting markets anywhere in the world．They sold goods from India, Africa, Japan, Korea, Turkey, Iran and other Arab countries and many items in the markets would have been completely new to some of the buyers．Interesting animals were sold together with exotic(奇异的)plants and strange medicines．Dried animals, dried foods and dried plants were laid out for sale next to rare seeds and spices(物种)．But besides the hope to trade, which drew people together, China was still largely a mysterious(神秘的)country to the outside world and certainly the secret of the silk making was still unknown． 　　The route(路线)to the west followed different paths but the traders would have traveled from places to places, always looking for routes both to water and protection．However, the Ming Dynasty had its policy of isolation(闭关), together with the growth of Islam(伊斯兰), reduced the traffic along this ancient land route．Instead, sea routes became more popular and in the early 15th century there were many Chinese ships trading silk and other goods along the coasts of India, Arabia and Africa． (1) This passage mainly wants to tell us _________． [　　] A． the silk trade in the past B． the rise and fall of the Silk Road C． the hard life the traders on the Silk Road D． why sea routes became popular in the early 15th century (2) It is probable that many dried goods were sold in the market because _________． [　　] A． the market traders could store them for longer time and sell them more easily B． they could be stored and transported more easily by the traders on the Silk Road C． they could be transported far more easily by traders from different countries D． they were lighter for the camels to carry wherever the traders wanted to go (3) By saying“China was still largely a mysterious country to the outside world”the author refers to the fact that _________． [　　] A． a large part of China was mysterious to the outside world B． China was a large country that was totally unknown to the outside world C． to a great extent China was little known or understood by the outside world D． most of China was misunderstood by the outside world