Mysterious ocean blob revealed to be a deepstaria enigmatica jellyfish | Daily Mail Online
Mystery solved: Curious blob filmed in the deep revealed to be a giant jelly fish (not a whale placenta)
15:57 GMT, 12 May 2012
16:18 GMT, 12 May 2012
A mysterious ocean 'blob', recorded by a deep-sea remote-controlled underwater camera, has been identified as a jelly fish.When a Youtube video of the creature was posted last month speculators suggested it was everything from the remains of a whale placenta to a fishing net.However, experts have now confirmed that the ‘sea monster’ is, in fact, a rarely studied jelly fish known as Deepstaria Enigmatica.
Identified: The mysterious creature has been revealed to be a deep sea jellyfish
Objects within: The creature is a rarely studied jelly fish known as Deepstaria Enigmatica
Unusual: The hexagonal markings on the creature implied the creature was not a jellyfish
Solved: The blob is a Deepstaria Enigmatica - a jelly fish which grows to approximately 60cm in widthThe creature created a mystery as it has organs and appendages never spotted on a jellyfish before.
The jellyfish, which are
approximately 60cm in width, are rarely seen intact, explains Steven
Haddock from the Monterey Bay Aquarium Research Institute.
'This bag-like jelly is not that rare, but is large, so rarely seen intact,' Haddock writes on the JellyWatch Facebook page.
'In the video, the swirling from the sub makes the medusa appear to undulate, and it even turns inside-out.'
Another expert, Craig McClain from
the National Evolutionary Synthesis Center, explains that the confusing
whitish lumps seen in the video are the jellyfish’s testicles.
The jellyfish was reportedly filmed
during deep-sea drilling near the United Kingdom. The species is usually
found approximately 5,000 feet below in the south Atlantic Ocean.
Previously it was suggested that the
floating blob could be a whale placenta, but the hexagonal shapes on the
skin made that unlikely.
RELATED ARTICLES
Share this article
Another guess was that the creature
might be a Stygiomedusa Gigantea. This type of jellyfish - which can
grow up to six metres in length - has only been spotted 114 times in 110
years, so details on it are scant.
But again, the appendages got in the way.
The animal’s brown stomach caused
further confusion, as Deepstaria enigmatica are typically colourless,
with one description saying the passages to the stomach are 'somewhat
irregular-edged, forming a reticulate network'.
The hexagonal markings on the top of
the creature led one commentator on the website Snopes - which tries to
debunk or confirm rumours - to suggest this is simply nothing more than a
fishing net.
Another mystery - a man-made one,
this time - is exactly where this video was filmed. It was added to
YouTube on April 27 this year, and appears to have been filmed two days
earlier, but the poster did not leave any other details about the
Bizarre: The creature had many bizarre appendages which have now been explained as testicles
Wrong: YouTube commentators suggested it may be a whale placenta
Other strange organs kept viewers scratching their heads but the mystery has now been solved
See the video here:
Read more:
Share or comment on this article
MOST READ NEWS
The comments below have not been moderated.
We are no longer accepting comments on this article.
More top stories
DON'T MISS
GADGET REVIEWS
Next story
SHARE PICTURE
Copy link to paste in your message这是个机器人猖狂的时代，请输一下验证码，证明咱是正常人~.第四部分: 任务型填空Teaching kids to fish sometimes puzzles us parents. Now I’d like to give you a few tips.First of all, start them young.Get them in a boat, or on a pier, or on the bank at as young an age 题目和参考答案——精英家教网——
成绩波动大？难提高？听顶级名师视频辅导，
& 题目详情
.第四部分: 任务型填空( 共10小题,满分10分)Teaching kids to fish sometimes puzzles us parents. Now I’d like to give you a few tips.First of all, start them young.Get them in a boat, or on a pier(码头), or on the bank at as young an age as you possibly can. Obviously this means being extremely conscious about their safety. Whatever you do, DON’T plan on any fishing yourself. If fishing is going to happen, the fishing will be done by the kids with your help! This lets you pay attention to them and not ignore them while you fish.Next, make sure you plan the first trips to someplace where you can actually catch a lot of fish. At this point, it doesn’t matter what kind or how big, just make sure they can catch some. A small child’s patience is very short, and waiting 30 minutes for a bite will turn them off in a hurry. You may need to go to a small pond where the fish are dying to eat bread balls. Any type of fish will do. Remember, this is for them, not for you.As they fish, cheer for every fish they catch. Make a really big deal out of it. Take pictures. And if it’s possible, take some home to clean. Let the child help you clean with a table knife, so he can’t get hurt.Make sure he makes and sees the connection from catching to cleaning to cooking. As soon as you have the fish cleaned, it’s into the kitchen to start cooking. Make him flour and cornmeal the fish. Let him see the fish cooking, and talk about how good they are. Then when it’s ready, make sure you brag（吹嘘） on the fact that he (or she ) caught these fish, and “aren’t they good?”In this way, I’m sure your kids will be interested in fishing and good at fishing.Title: Teach a kid to fish&Start them young·Be aware of (71)_________·Plan a fishing trip for the (72)_________ not for yourself. &Plan the first fishing (73)_______·Choose places where the kids can catch fish easily because a small child’s patience doesn’t (74)_________ long. ·Regardless of (不管)the kind and (75)_________ of fish.&Cheer for every fish they catch·Make a big deal out of it.·Take pictures. ·Take some home and let the child help to clean with a table knife to avoid (76)_________ hurt.(77)_________ the fish they catch·(78)_________him to flour and cornmeal the fish.·Let him see the fish cooking.·Talk about how good they are.(79)_________·Make them (80)_________ in and good at fishing.
71.safety&& 72.kids&& 73.trips&&&& 74.last&& 75.size&&& 76.getting&& 77.cook&& 78.get&& 79.conclusion&& 80.interested&&略
请在这里输入关键词：
科目：高中英语
来源：不详
题型：完形填空
第二节&&完形填空（共20小题；每小题2分，满分40分）阅读下列短文，掌握其大意，然后从36—55各题的四个选项（A、B、C和D）中选出能填入相应空白处的最佳选项。并将答案写在答题卡上。John Henry was a young man, and he was one of the best steel-drivers in the country,He cjould work for hours without missing a beat, People said he worked so fast that his& 36&&& moved Like lightening One day,a salesman came to the work area with a new&& 37&&& machine by powered steam, He said it could drill holes&&& 38&& than twelve men working together, The railroad company& 39 to buy the machine if it worked as well as the salesman said.The supervisor(监工头) said,”I have the best steel-driver in the&& 40&&&& , He can beat more than twenty men working together,”The salesman&& 41&&& the statements. He said the company could have the machine without cost&& 42&&& he was faster, The supervisor told John about it and said “How about a&& 43&&& ?” John Henry looked at the machine and saw&& 44&&& of the future, He saw machines taking&& 45&&& of America’s best laborers, He saw himself and friends&& 46&& and standing by a road ,asking for food, He saw men losing their families and their&&& 47&&& as human beings , John Henry told the supervisor he would never let the machine take his job, His friends all cheered.The competition began, John Henry& 48&& his hammer and started working. At first, the steam-powered drill worked two times faster than he did,&&& 49&&&& he started working with a hammer in each hand. He worked faster and faster. In the mountain , the dust was so&&& 50&& that most men would have had trouble&& 51&&& . After a while , the machine was pulled from the tunnel , It had broken down, . But John Henry&& 52&&& working faster and faster. At last he became weak ,and his heart&&& 53&&& . John Henry fell to the ground .”I beat them,” Then he took his 54&&& breath.Soon, the steam drill and other machines replaced the steel-drivers ,.Many&& 55&& left their families, looking for work, They took the only jobs they could find, As they worked, some sang about John Henry,36.A& broom,&&&&&&&&&& B& hammer&&&&&&&&& C hand&&&&&&&& D sleeve37.A washing&&&&&&&&&&& B drilling&&&&&&&&&&&& C sewing&&&&&&& D flying38. A quickly&&&&&&&&&&& B slower&&&&&&&&&&&&& C faster&&&&&&&& D fast39. A managed&&&&&&&&&B allowed&&&&&&&&&&&&&C refused&&&&&& D planned40 A family&&&&&&&&&&&& B class&&&&&&&&&&&&&&&C film&&&&&&&&&& D country41. A doubted&&&&&&&&& B hated&&&&&&&&&&&&&&&C disagreed&&&&&&D decided42. A when&&&&&&&&&&&& B if&&&&&&&&&&&&&&&&&& C unless&&&&&&&&& D despite43. A lesson&&&&&&&&&&&& B race&&&&&&&&&&&&&&& C unless&&&&&&&& D despite44.A images&&&&&&&&&&& B faces&&&&&&&&&&&&&&& C plans&&&&&&&&& D signs45. A the place&&&&&&&& B the room&&&&&&&&&&&& C the space&&&&&&&D the air46. A excited&&&&&&&&&B unemployed&&&&&&&&&&C moved&&&&&&&&&D encouraged47. A food&&&&&&&&&&&& B rights&&&&&&&&&&&&&&C wages&&&&&&&D houses48.A touched&&&&&&&&&& B kicked&&&&&&&&&&&&& C kissed&&&&&&&&D stamped49. A Otherwise&&&&&&&& B But&&&&&&&&&&&&&&&C Then&&&&&&&&&&D However50. A thin&&&&&&&&&&&&&& B big&&&&&&&&&&&&&&&C high&&&&&&&&&&D thick51. A laughing&&&&&&&&& B talking&&&&&&&&&&&&&C breathing&&&&&&D singing 52.A stopped&&&&&&&&&& B kept&&&&&&&&&&&&&&&&C enjoyed&&&&&&&D suggested53. A burst&&&&&&&&&&&&& B worked&&&&&&&&&&&&C ran&&&&&&&&&&&D lived54.A& own&&&&&&&&&&&&& B deep&&&&&&&&&&&&&&C best&&&&&&&&&&D last55. A laborers&&&&&&&&&&B women&&&&&&&&&&&&&C villagers&&&&&& D salesmen
科目：高中英语
来源：不详
题型：完形填空
根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。What is your favourite colour? Do you like yellow, orange, red? 小题1:Do you prefer greys and blues? Then you are probably quiet, shy, and you would rather follow than lead. You tend to be a pessimist（悲观主义者）. At least, this is what psychologists tell us, and they should know, because they have been seriously studying the meaning of colour preference, as well as the effect that colours have on human beings. 小题2:If you happen to love brown, you did so, as soon as you opened your eyes, or at least as soon as you could see clearly.小题3:. A yellow room makes most people feel more cheerful and more relaxed t and a red dress brings warmth and cheer to the saddest winter day. 小题4:. A black bridge over the Thames River, near London, used to be the scene of more suicides(自杀) than any other bridge in the area---until it was repainted green. The number of suicide attempts immediately fell sharply. Perhaps it would have fallen even more if the bridge had been done in pink or baby blue.小题5:It is an established fact that factory workers work better, harder, and have fewer accidents when their machines are painted orange rather than black or grey.A．On the other hand, black is depressing.B．They tell us, among other facts, that we do not choose our favourite colour as grow up --- we are born with our preference.C．The rooms are painted in different colours as you like.D．If you do, you must be an optimist, a leader, an active person who enjoys life, people and excitement.E. Light and bright colours make people not only happier but more active.F. Life is like a picture or a poem, full of different colours.G. Colours do influence our moods---there is no doubt about it.
科目：高中英语
来源：不详
题型：阅读理解
.Some years ago on a hot summer day in south Florida a little boy decided to go for a swim in the old swimming hole behind his house. He flew into the water , not realizing that as he swam toward the middle of the lake, an alligator (鳄鱼) was swimming toward the shore. His mother in the house was looking out the window and saw the two as they got closer and closer together . She ran toward the water , shouting to her son as loudly as he could Hearing her voice , the littler boy became alarmed and made a U-turn to swim to his mother. It was too late. Just as he reached her, the alligator reached him.From the dock, the mother grabber her little boy by the arms just as the alligator snatched his legs. That began an incredible tug-of –war between the two. The alligator was much stronger that the mother , but the mother was much too passionate to let go . A farmer happened to drive by, heard her screams, raced from his truck, took aim and shot the alligator. Remarkably, after weeks and weeks in the hospital, the little boy survived. His legs were extremely scarred by the vicious attack of the animal and, on his arms, were deep scratches where his mother’s fingernails dug in to his flesh in her effort to hang on to the son she loved. The newspaper reporter who interviewed the boy after the trauma (创伤)， asked if he would show him his scars. The boy lifted his pant legs. And then, with obvious pride, he said to the reporter, “ But look at my arms. I have great scars on my arms, too. I have them because my mum wouldn’t let go。“Sometimes we foolishly wade into dangerous situation. The swimming hole of life is filled with peril (危险)and we forget that the enemy is waiting to attack. When the tug-of –war begins and if you have the scars of his love on your arms, be very, very grateful. He did not —and will not—let you go.60. What was coming when the boy flew into the river?A. Happiness.&&&& B. A fish& C. Danger&&&&& D. Mother61. The underlined word “ passionate” in paragraph 4 means“ __________”A. anxious&&&&&& B . eager& C. curious&&&&& D. full of emotion62.Which of the following is TRUE according to the passage?A. The scars on his arms are great.B. The boy is sad because of his scars.C. His mother is stronger that the alligator.D. The scars on the boy were caused by the alligator.63. Which of the following can serve as the best title for the passage?A. Save a boy.&&&&&&&&&&&B. Scars of love&&C. Fight with an Alligator&& D.A brave boy
科目：高中英语
来源：不详
题型：阅读理解
You Mi, a lovely and confident 17-year-old student, is the first Chinese high school student to appear on the cover of the popular young adults’ fashion magazine Seventeen.　　“You is IN,” said Wang Lihua, Editor-in-Chief of Seventeen. “She is active and mature because of her knowledge on everything from academic studies, to books on art, to movies. We found she’s the very style we’re looking for to represent young people’s attitudes.”　　You also impressed Wang with her fluent English when they first met last year. As the hostess of an English broadcasting programme at the High School Affiliated to Renmin University, You is always praised for speaking English almost like a native speaker. “I’ve built up my English by watching thousands of English DVDs since I was 10,” she explained.　　But for You, watching isn’t enough. Last year, while in Senior 1, she met a talented boy who showed self-made DV movies at the English Corner in her school.　　“I thought it was so cool and I knew that I should start making my own films,” she said. So she wrote a campus story, persuaded schoolmates to star in it and then began shooting a 30-minute DV movie, all in English. “I played one of the leading roles, actually I was everything in my film. I worked on it every single day during the SARS holidays,” she recalled. The movie finally became a big hit on campus, earning You a strong reputation as a DV movie director.　　But this is not the only field she wants to master. Despite being a science student, You likes art, literature and fashion design very much.　　“There are people who can be artists, there are people who edit books, and there are people who become film producers. But I just hope to mix all the things up!” she said. “There is an old saying I believe: Chance favours only the prepared mind.”51. You Mi was chosen to be a cover of Seventeen, mainly because she _____.A. is beautiful&&&&&&&&&& B. she is lovely and full of confidenceC. is active and mature&&& D. has rich knowledge52. The author mentioned a talented boy to show _____.A. the great influence he had on You Mi&B. he was admired by his schoolmates　C. the young can do things as well as the adults do&D. self-made DV movies are popular at school53.In the 30-minute DV movie, You Mi didn’t act as a(n) _____.A. director&& B. musician& C. actress& D. producer54. We can learn from the passage that _____.A. You Mi hopes to be a mixed talentB. the success of a 30-minute DV movie shocked You MiC. You Mi dreams of becoming a scientistD. the outbreak of SARS delayed You Mi’s studies
科目：高中英语
来源：不详
题型：阅读理解
Ⅲ&阅读（共两节。满分40分）第一节&阅读理解（共15小题；每小题2分，满分30分）阅读下列短文，从每题所给的A、B、C和D项中，选出最佳选项，并在答题卡上将该项涂黑。The idea about the phoenix goes back to Ancient Egypt, where we find the phoenix described as a handsome, eagle-like bird, with part-golden, part-red plumage, that spent most of its life in the Arabian deserts. It was rarely seen and according to one version of the story, only appeared in Egypt once every five hundred years, when it flew to Heliopolis, “city of the sun”, and deliberately burnt itself to ashes by settling on the altar(祭坛) flame there! However, it seems it did not really die because from those same ashes a young, fully formed phoenix was born and flew away, apparently back to Arabia.It is pretty obvious that no one has ever seen or will see a living phoenix. The interesting thing is that we can find certain clues which may explain one aspect of the Egyptians’ idea. It may sound unbelievable, but some birds are apparently quite charmed by flames and small fires, especially members of the crow family. One zoologist actually proved this by setting fire to some straw near to a tame（驯养的） rook. Far from becoming nervous and backing away, the bird deliberately stood over the flames, with raised and vibrating wings. It didn’t get burnt, but the image it presented by its strange behavior was almost exactly like that shown in illustrations of the mythical phoenix! Why birds should occasionally behave in this strange way is not clear. One idea is that they carefully use the heat of the flames to relieve the annoyance caused by their feather mites(虱) which all birds have. Whatever the reason, it is quite possible that the Ancient Egyptians saw birds behaving in this way, from time to time, and used it as the basis of their phoenix myth, adding fanciful details which closely linked it to their worship of the sun and their belief in resurrection. Nowadays, the phoenix is much less important to us than it was to the Egyptians. But the logo of modern fire insurance companies, which employ the phoenix as one of their symbols, refers that in one sense the idea of it remains.&&41. According to the passage, the phoenix ______________ . A. is a handsome and eagle-like bird living in Arab B. used to be seen when the Egyptians held religious activities C. has never really existed in the world
D. is the king of all kinds of birds42. The reason why birds stand above flames is probably that _____________ . A. the phoenix used to do so B. they may get rid of the mites C. they want to burn their feather
D. they can heat themselves43. Which of the following statements is NOT correct? A. The ancient Egyptians worshiped the phoenix. B. The scientists have discovered why birds are attracted by fire.
C. The modern people still favor the idea of the phoenix. D. The mythical tales about the phoenix were based on facts. 44. Which of the following is closest to “resurrection” in the 3rd paragraph? A. living forever&&&&&&& B. offering warmth&&&&&&& C. coming back to life&&&&&&&&& D. staying healthy45. What does the phoenix probably mean in the logo of a fire insurance company? A. Our company can protect you from being harmed by fire. B. If your property is destroyed by fire, we will help you build it up again. C. Our company will always be energetic and wealthy.
D. If needed, we will save you at the risk of losing lives.
科目：高中英语
来源：不详
题型：阅读理解
.English and Spanish Lessons&￡20If you want to learn or improve your English or Spanish, this is what you arelooking for! One-to-one and small group lessons are created to meet your needs. If youwant to take an Academic English exam(FCE, CAE, IELTS), improve your accent, or.just learn the language, this is perfect for you. Students with all levels are welcome.Private Language Tuitions and Translations ￡20Welcome to HL Linguistic Connection! We take great pride in delivering thebest-quality training, translation services. Our highly qualified and experienced teamoffers you one-to-one or group tuitions at your office or home. Please contact us andarrange an assessment meeting. We provide a number of customized(定制的) coursesfor Beginner, Intermediate. Advanced and Higher level students in the followinglanguages: Spanish, French, Italian and Portuguese. Please feel free to visit our website:
As soon as you contact us, you will receive a brochure(手册) with fullinformation regarding courses, date, fees and special offers.Information Event About the Marriage Course ￡O.OOMarriage course party/information evening 8 pm December lst at Wesleys, HighStreet Harpenden-food and video clips for anyone interested in 7-week coursestarting January 26th (Mondays 7:30-9:45pm) to learn how to enrich your marriage. Sight and Sound of a Winner&￡5 Read and discover how to live as a Winner: overcoming obstacles(障碍）andoppression(压抑), your vision must change. This is because as a man thinks in hisheart so is he.41. If Wu Dong will take an LELTS exam, which advertisement will attract him? A. English and Spanish Lessons. B. Private Language Tuitions and Translations.&&&&& C. Information Event about the Marriage Course, D. Sight and Sound of a winner.42. How can you get full information about Private Language Tuitions and Translations? A. By visiting its office.&&&&&&&&& B. By readjng its brochure.C. By sending a fax.&&&&&&&&&&&& D. By making a phone call.43. The underlined word "Intermediate" in Paragraph 2 is closest in meaning to "_______". A. Basic&&&&&&&&&&&&&&& B. Medium&&&&&&&&&&&& C. Junior&&&&&&&&&&&& D. Senior44. According to the text, we can learn that ________________. A. HL Linguistic Connection is an online school B. HL Linguistic Connection is not suitable for beginners C. Information Event About the Marriage Course is free D. Sight and Sound of a winner is about English study
科目：高中英语
来源：不详
题型：阅读理解
.Nate suffered a hard blow when he lost his job．His boss had spoken rudely, “Your services are no longer needed.” Nate left the building filled with despair．By the time he reached home, he was in a deep depression．When he entered his house, he blurted out to his wife Sophia, “I lost my job．I am a complete, utter failure.” A tense silence followed．Then a smile crept across Sophia’s face．“What great news!” she responded.“Now you can write the book you have always wanted to write.”“But I have no job and no prospect of a job,” YC he objected, completely without hope．“If I struggle to be an author, then what will we live on? Where will the money come from?” Sophia took her husband by the hand and led him to the kitchen．Opening a drawer, she took out a box that was full of cash．“Where on earth did you get this?” Nate gasped．“To whom does it belong?”“It’s ours!” Sophia replied．“I always knew that one day you would become a great writer if only you were given the chance．From the money you gave me for housekeeping every week, I have saved as much as I could so you would have your chance．Now there is enough to last us a whole year.”What a surprise! What encouragement! What a wife! The unemployed husband did concentrate on writing that year, and the novel he wrote became a literary masterpiece．The book is The Scarlet Letter．Sophia had an even greater achievement, and she turned Nathaniel Hawthorne from a poor clerk into a world famous master．&&68．Which of the following can be inferred from the first paragraph?
A．Sophia was very disappointed to hear the news&& B．Nate was too sad to speak any more C．Sophia was thinking of how to encourage Nate&& D．Neither husband nor wife had any idea what to do69．Sophia saved money because _______________________． A．she knew her husband would lose his job one day&& B．she knew their life would be in difficulty C．she was very careful with money&& D．she was trying to help her husband in every possible way70．From the passage we can know that Sophia was __________________________． A．kind and brave&&&&&&& B．careful and encouraging C．friendly and warm-hearted&&&&& D．honest and determined71．What would be the best title for the passage? A．Sophia’s Achievement && B．A Great Writer’s Struggle to Success C．Great Encouragement in Hard Times &&& D．Failure is the Mother of Success
科目：高中英语
来源：不详
题型：阅读理解
.Nuclear power's danger to health, safety, and even life itself can be d radiation(辐射).
Nuclear radiation has a certain mystery about it, partly because it cannot be detected (探测) by human senses. It can't be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around us but we can't detect them, sense them, without a radio receiver. Similarly, we can't sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things.
At very high levels, radiation can kill an animal or human being completely by killing masses of cells in important organs (器官). But even the lowest levels can do serious damage. There is no level of radiation that is completely safe. If the radiation does not hit anything important, the damage may not be significant. This is the case when only a few cells are hit, and if they are killed completely. Your body will replace the dead cells with healthy ones. But if the few cells are only damaged, and if they reproduce themselves, you may be in trouble. They reproduce themselves in an unusual way. They can grow into cancer. Sometimes this does not show up for many years. This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the knowledge of the person at the time that damage has occurred. A person can be irradiated(放射治疗) and feel fine, then die of cancer five, ten, or twenty years later as a result. Or a child can be born weak or easy to get serious illness as a result of radiation absorbed by its grandparents.
Radiation can hurt us. We must know the truth. 68. According to the passage, the danger of nuclear power lies in __________. A. nuclear mystery &&&&&&&&&&&& B. radiation detection C. radiation level &&&&&&&&&&&&&&& D. nuclear radiation 69. Radiation can lead to serious results even at the lowest level ________. A. when it kills few cells &&&&&&&&&&& B. if it damages few cells C. though the damaged cells can repair themselves D. unless the damaged cells can reproduce themselves 70. Radiation can hurt us in the way that it can _____. A. kill large numbers of cells in main organs so as to cause death immediately B. damage cells which may grow into cancer years later C. affect the healthy growth of our younger generation D. lead to all of the above results71. Which of the following can be best inferred from the passage? A. The importance of protection from radiation can be overemphasized (过分强调). B. The mystery about radiation remains unsolved. C. Cancer is mainly caused by radiation. D. Radiation can hurt those who do not know about its danger.
精英家教网新版app上线啦！用app只需扫描书本条形码就能找到作业，家长给孩子检查作业更省心，同学们作业对答案更方便，扫描上方二维码立刻安装！}