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假设两个氘核在一直线上相碰发生聚变反应生成氦的同位素和中子，已知氘核的质量是2.013 6u，中子的质量是1.008 7u，氦核同位素的质量是3.015 0u． （1） 聚变的核反应方程式是，在聚变核反应中释放出的能量为 MeV．（保留两位有效数字） （2） 若氚核和氦核发生聚变生成锂核，反应方程式为 H+ He→ Li，已知各核子比结合能分别为EH=1.112MeV、EHe=7.075MeV、ELi=5.603MeV，求此核反应过程中释放的核能．This is the VOA Special English Education Report. A few weeks ago, we talked about the Test of English as a Foreign Language, or TOEFL. A listener in Cambodia named Thida asks if American colleges and universities also accept the IELTS exam. IELTS is the International English Language Testing System. It was developed by the University of Cambridge ESOL examiners.Cambridge ESOL says the test measures true-to-life ability to communicate in English for education, immigration or employment. The IELTS tests listening, reading, writing and speaking skills. It uses a mixture of accents and spellings, including British English and American English.The test is used by government agencies, schools and professional organizations in one hundred and twenty countries. And, yes, that includes the United States. The many American schools that accepted the IELTS can be found on the Web at felts.org.Some schools accept both the TOEFL and the IELTS, but the graduate school at Duke University in Durham, North Carolina, for example, says it prefers the IEITS.The listening and speaking parts are the same for everyone who takes the IELTS, but people have a choice of reading and writing tests -- either academic or general training.The listening test takes thirty minutes. There are forty questions based on a recording. The reading test takes sixty minutes. Students answer forty questions based on three written passages.The writing test also takes sixty minutes. Students have to write two essays. One essay has to be at least one hundred and fifty words long and the other at least two hundred and fifty words. The shorter one is description of something; the longer one has to support and argument.The speaking test takes less than fifteen minutes. The score is based on a recorded talk between the student and a test examiner.And that's the VOA Special English Education Report, written by Nancy Steinbach. If you have a general question for our series, write to special@voanews.com. I'm Barbara Klein.【小题1】What does TOEFL stand for?A．The Voice of AmericaB．The International English Language Testing SystemC．The Test of English as a Foreign LanguageD．The Test of English as a Native Language【小题2】The International English Language Testing System commonly takes _______ in all.A．less than 160 minutesB．more than 165 minutesC．no more than 160 minutesD．less than 166 minutes【小题3】 According to the passage, we can infer _______.A．IELTS is efficient and necessary if you want to go to English-speaking countriesB．IELTS is completely different from TOEFLC．every American needs to accept TOEFLD．IEITS isn't used more widely than TOEFL【小题4】What is the main idea of the passage?A．How can the readers write papers to the VOA programme?B．It talks about some ways to pass TOEFL.C．It introduces IELTS.D．How can the readers pass two kinds of tests?