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常见的三种模拟滤波器中，在通带和阻带内具有等波纹变化的是切比雪夫滤波器。
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输入大量库血应防止发生:
输血引起溶血反应的主要表现是
P175Task 2 The words in bold are from Listening Skills &Strategies in this part. Listen to their explanations. Then complete each sentence with the correct word. You may change the form when necessary.B Intelligence refers to the ability to learn, understand, and think about things.C Transmit means to send out messages, etc. using radio, television, or other similar equipment.D. Aliens are relating to creatures from another planet.E. Deluge means a large amount of something such as letters or questions that someone gets at the same time.F. Antenna is a wire rod, etc. used for receiving radio and television signals.1. In 1969, the first pictures of Mars were to the Earth by the spacecraft Marine 6.2. Villagers look like they will be losing their main bus service in just over a fortnight, despite a(n) of complaints to the bus company.3. Astronomers call the thousands of tons of particles that fall to the Earth annually cosmic dust.4. Wireless call can be received by a number of different miles away from the caller5. John could be energetic and and he had a number of impressive successes, but he was incapable of either sustaining or capitalizing on these.6. The thought of the first contact with a(n) race only through their aircraft is one that is close to the heart of science fiction.[音频]
P178[音频]Task 2 The words in bold are from Listening Skills & Strategies in this partListen to their explanations. Then complete each sentence with the correct word.A. Forefront refers to the most noticeable or important position.B. Plummet means to decrease in value or amount.C. To shroud is to hide something or cover something.D. If an object or a substance is translucent, it is not transparent, but clear enough to allow some light to pass through.E. An armada is a large group of things.F. Something mind-boggling refers to something extremely surprising and difficult to understand or imagine.G. Volatile as a technical word describes the quality of liquid or solid substance that changes easily into a gas.H. A perception is a thought, belief, or opinion, often held by many people and based on appearances.1. While the intense competition that marked the early years of space no longer exists, experts agree Sputnik forever changed the of outer space and its possibilities.2. Tropical Storm Lee brought rain and wind, causing temperatures to3. Carrie's skin is .Blue veins run visibly beneath it like a roadmap to her heart.4. SJCOOP alumni like Maxwell are increasingly impacting their colleagues in newsrooms across the continent and successfully thrusting science to the of news shows.5. The new kind of telescope was designed to penetrate the curtains of the dust and the gas that galaxies, swirl around stars, and stretch through the expanses of interstellar space.6. Carbon dioxide, water and other substances are believed to have been degassed from the Earth in its early history of formation and cooling.7. The only galaxy that can be seen by the naked eye from Arches National Park is M31, better known as Andromeda, which is 2.5 million light years away.8. For nearly a year, the international has been successful in keeping many ships from being hijacked.
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