Space is a dangerous place, not only because of meteors   but also because of rays from the sun and other stars. The atmosphere again acts as our protective blanket on earth. Light gets through, and this is necessary for plants to make the food that we eat. Heat, too, makes our environment endurable. Various kinds of rays come through the air from outer space, but enormous quantities of radiation from the sun are screened off. As soon as men leave the atmosphere they are exposed to this radiation but their spacesuits or the walls of their spacecraft, if they are inside, do prevent a lot of radiation damage. Radiation is the greatest known danger to explorers in space, The unit of radiation is called "rem" Scientists have reason to think that a man can put up with far more radiation than 0.1rem without being damaged; the figure of 60 rems has been agreed on. The trouble is that it is extremely difficult to be sure about radiation damage. A person may feel perfectly well, but the cells of his or her sex organs may be damaged, and this will not be discovered until the birth of _ children or even grandchildren. Missions of the Apollo flights have had to cross belts of high radiation and , during the outward and return journeys, the Apollo crew accumulated  a large amount of rems. So far, no dangerous amounts of radiation have been reported, but the Apollo missions have been quite short. We simply do not know yet how men are going to get on when they spend weeks and months outside the protection of the atmosphere, working in a space laboratory. Drugs might help to decrease the damage done by radiation, but no really effective ones have been found so far. It can be inferred from the passage that  _  . A) the Apollo mission was very successful B) astronauts will have deformed children or grandchildren C) protection from space radiation is no easy job D) radiation is not a threat to well-protected space explorers
C
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As a volunteer, you will discover the unique opportunity of visiting the real world beyond the tourist window and became immersed in the culture you visit. For most travelers, this time spent working on meaningful projects, and getting to know the local area and its people, is often cited as their most memorable, enjoyable and fulfilling life experience. Who can volunteer? Kaya Volunteers are 18-80 years old people with an adventurous spirit. Whether you have time for a 2-week trip or a 6-month break, travelling on your own, with a group or with your family, or you are a student, taking a break from your job, or have even retired, they will find a project that can use your help. Countries where you can volunteer: Asia-Pacific (Australia, India, Indonesia, Nepal, New Zealand, the Philippines, Thailand, Vietnam.) Africa  (Botswana,Ghana,Kenya,Mozambique,South Africa,Zambia,Zimbabwe) Latin America  (Belize,Bolivia,Brazil,Costa Rica,Ecuador,Peru) What type of projects can you do? Kaya's Project advisors work with you to decide which project is best for you and what type of work you would like to do. you can work in the following fields: Environmental preservation- From the Ecuadorian rain forest to the jungles of Thailand, repair the damage done to some of the most beautiful and diverse places on earth. Work with children- They have over 40 projects working with children across the world in orphanages, schools and shelters for the abused, disabled and disadvantaged. Sports - Through sports, their projects that can provide opportunities for health education and the development of life skills, such as teamwork, communication, discipline and self- confidence. Education - From English teaching to education programs for special needs and minority groups, give greater opportunity to the disadvantaged through education. All projects include airport pick-ups and drop-offs, accommodation, orientation and 24-hour support. Many of their placements also include all meals and some language classes so that you can get even... Some voluntary placements offer free meals and language classes to   _  . A) attract more people to do voluntary work. B) encourage voluntary as to work harder. C) save more money for the volunteers. D) help volunteer get more involved.
D
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Future Life Pets By DogTown Media, LLC Open iTunes to buy and download apps. *Price: $2.99 *Category: Lifestyle *Updated: Jan 07, 2012 *Version: 1.1 *Size: 36.3 MB *Language: English *Seller: DOG TOWN MEDIA *(c) DogTown Media LLC Description DISCOVER FUTURE LIFETIMES WITH YOUR PETS You can be transported into the future to be reunited with your pet in another place and time. As an internationally recognized psychic  and best-selling author, Anne Jirsch will be your guide in this fascinating meditation   game. Future Life Pets will take you into a state of deep relaxation to help you understand this special condition. With expert hypnosis   you can discover how your paths will cross in your future lifetime. WHAT PEOPLE ARE SAYING "I immediately saw I was riding a tall black and white horse and you've guessed it --it was my dog and this time he was bigger than ever." --Mike from Kansas City. "Seeing both my cats in the future lifetime has given me so much joy. They are both cats again next time around, only a lot bigger and smoother. I clearly saw them both lie by my feet just as they do right now." --Felicity from Manchester, UK. The regular buyers of Anne's products include heads of industry, politicians, and celebrities of all kinds. She is a world famous psychic and author of three books Instant Intuition, The Future is Yours, and Cosmic Energy. More than a billion people in the world believe in the truth of meditation, through which we'll gain a greater understanding of our pets and ourselves. Prepare for the experience as the results are astonishing. The tall horse that Mike saw in his meditation is   _  . A) a dead dog B) his pet dog C) his pet horse D) a true horse
B
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Almost 80% of the Americans have stated their opposition to cloning pet animals such as cats and dogs, yet companies still try to make a business out of selling cloned pets. Pet cloning has been promoted as a way to "bring back" or "copy" a beloved companion animal. However, studies have shown that cloning remains an experimental technology with many failures. Behind each lovely picture of a cloned cat or dog lie hundreds of animals that were kept in lab cages, receiving bad treatment to produce just that one cloned animal. For all that, you end up with a cloned animal who is unlikely to appear like the original physically or behaviorally and may experience serious health problems. Also, while pet cloning companies are charging customers up to $150,000 for a cloned pet, millions of homeless animals of the same species are available in US animal shelters for around $100. Unfortunately, most of these animals are killed for lack of adopting homes. With No Pet Cloning campaign, the American Anti-Vivisection Society (AAVS) tries to protect both animals and people from harm. They campaigned until the US companies that sold cloned animals closed their doors. First it was Genetic Savings & Clone Inc. and then it was BioArts International. When BioArts was closed, its owner, Lou Hawthorne, finally had to _ the problems of pet cloning. According to Hawthorne, he has seen numerous failures during his pet cloning attempts, "One clone----which was supposed to be black and white----was born greenish-yellow where it should have been white (we still have no good explanation for how that happened)." The AAVS is educating the public about the animal suffering and is seeking regulation of cloning activities. They will continue to take the lead in protecting animals from the threats of pet cloning. From the passage, we know that   _  . A) pets are often deserted by their owners B) more and more people have joined the AAVS C) most American are against cloning pet animals D) the American Anti-Vivisection Society is supported by the government

C
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