题干

某照明灯额定电压是 36V,正常发光时灯丝电阻为 24Ω,则照明灯的额定电流是____ A.如果电源电压是 48V,为使照明灯正常发光,可以在电路中串联一个阻值____Ω的 电阻,此时电阻在 10s 内产生的电热是____J.
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1.5,8,180

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完形填空

    A Race Against Death

    It was a cold January in 1925 in Nome, Alaska. The town was cut off from the rest of the world due to heavy snow.

    On the 20th of that month, Dr. Welch 1 a sick boy, Billy, and knew he had diphtheria, a deadly infectious(传染的) disease mainly affecting children. The children of Nome would be 2 if it struck the town. Dr. Welch needed medicine as soon as possible to stop other kids from getting sick3 the closest supply was over 1,000 miles away, in Anchorage.

    How could the medicine get to Nome? The town's 4 was already full of ice, so it couldn't come by ship. Cars and horses couldn't travel on the 5 roads. Jet airplanes and big trucks didn't exist yet.

    6 January 26, Billy and three other children had died. Twenty more were 7 Nome's town officials came up with a(n)8. They would have the medicine sent by9 from Anchorage to Nenana. From there, dogsled(狗拉雪橇) drivers—known as “mushers”—would 10 it to Nome in a relay(接力).

    The race began on January 27. The first musher, Shannon, picked up the medicine from the train at Nenana and rode all night.11 he handed the medicine to the next musher, Shannon's face was black from the extreme cold.

On January 31, a musher named Seppala had to12 a frozen body of water called Norton Sound. It was the most13 part of the journey. Norton Sound was covered with ice, which could sometimes break up without warning. If that happened, Seppala might fall into the icy water below. He would14 and so would the sick children of Nome. But Seppala made it across.

    A huge snowstorm hit on February 1. A musher named Kaasen had to brave this storm. At one point, huge piles of snow blocked his15 He had to leave the trail (雪橇痕迹)to get around them. Conditions were so bad that it was impossible for him to 16 the trail again. The only hope was Balto, Kaasen's lead dog. Balto put his nose to the ground,17 to find the smell of other dogs that had traveled on the trail. If Balto failed, it would mean disaster for Nome. The minutes passed by. Suddenly, Balto began to 18 He had found the trail.

    At 5:30 am on February 2, Kaasen and his dog 19 in Nome. Within minutes, Dr. Welch had the medicine. He quickly gave it to the sick children. All of them recovered.

Nome had been20

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    Beijing residents could be rewarded with up to 500,000 yuan if they can provide useful information on spies or related activities, according to a government policy that took effect on Monday.

    Under the policy, informants will be offered rewards ranging, from 10,000 yuan to 500,000 yuan, depending on how useful the information is, according to the policy issued by the National Security Bureau(安全局) of Beijing. Informants can pass information to authorities by calling a hotline, sending letters or visiting the bureau.

    Informants' privacy and information about spy-related messages will not be disclosed, while information providers can ask authorities for protection if they or their relatives are in danger due to the act of informing, according to the policy.

    However, informants will face punishments if they slander (诽谤) others on purpose or invent and spread false information, the policy states clearly.

    The bureau said that China is witnessing rapid increases in international exchanges and the number of people entering or exiting the country each year. "Meanwhile, overseas espionage agencies(间谍机构)and other unfriendly forces have also strengthened their disruptive(破坏的) activities in China, including political, economical and military information." it said.

    Some Chinese individuals have also betrayed the nation to benefit their private interests, which offers overseas espionage agencies opportunities, the bureau said, adding that Beijing is the primary location for such activities. Therefore, it's necessary to take new measures in anti-espionage investigation, and to encourage the participation of the general public.

    One of the most recent cases made public occurred in the eastern province of Jiangsu in January. Two residents in Lianyungang city, surnamed Zhang and Wan, called the national security authorities after they found a device with instructions in foreign languages while fishing in the Yellow Sea. The device was later found to be spying equipment made and used by overseas agencies to collect data, according to an official release.

    China has strengthened legislation(立法) on State security in recent years. Facing a more complex State security situation, in 2014, the Standing Committee of the National People's Congress adopted the Counterespionage Law.