Why does the author mention "cosmic rays"?
Giải bởi qa.haylamdo.com
Tại sao tác giả lại đề cập đến "tia vũ trụ"?
A. Để giải thích vũ trụ bắt đầu như thế nào.
B. Để giải thích sự phong phú của hydro trong vũ trụ.
C. Là một phần của danh sách những thứ có chứa heli.
D. Như một ví dụ về câu đố thiên văn chưa giải quyết.
Đáp án: C
Giải thích: “Helium has been found in old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars. Helium nuclei have also been found to be constituents of cosmic rays that fall on the earth...”: Helium đã được tìm thấy trong các ngôi sao cũ, ở những ngôi sao tương đối trẻ, trong khí liên sao và trong các vật thể ở xa gọi là chuẩn tinh. Hạt nhân helium cũng đã được thấy là thành phần của các tia vũ trụ rơi xuống trái đất...
Read the following passage and mark the letter A, B, C, or D on your answer sheet to choose the word or phrase that best fits each of the numbered blanks from 25 to 29
Tourism is a big business. Millions of people around Europe spend their winters planning their destinations for the following summer, and their summers (25) ___________ to foreign climes for two weeks in the sun. They are the modern-day descendants of the aristocrats and the wealthy who would take months to complete the "Grand Tour” of Europe. But unlike their forefathers, tourists these days get a bad press. They're not (26) ___________ in the local culture, we're told they're just after the chance to behave a bit more wildly than they do at home. What's more, they damage the local environment and don't respect the locals and their way of life.
But are tourists really to blame? (27) ___________is it the fault of the tourist industry, which has failed to provide reasonably-priced alternatives? And if the local resort only offers a succession of bars for the tourists to visit, can we really criticize them for not doing more cultural activities? One holiday company, Far and Away, claims that tourists are crying out for more cultural holidays and believes that it has (28) ___________to come up with a range of package holidays which are affordable, culturally interesting, and environmentally friendly. Their brochure, which is to be (29) ___________ later this month, offers 200 holidays based on cultural themes, including history and architecture, learning the language, meeting the locals.
Not only my study but my hobbies also really keep me occupied every time.
It is the recommendation of many psychologists that a learner ought to use mental images to associate words and remember them.
Mark the letter A, B, C, or D to indicate the sentence that is closest in meaning to each of the following questions
"He is always arguing with his new classmate”. She said.
Before giving presentation, always ___________ the focus on the projector so that everyone can read what is on the screen.
In the early years of the 20th century, several rebellions ___________ in the northern parts of the country.
The government issued a warning to local companies that all waste must be disposed of___________ or they will face heavy fines.
Is anyone checking your essay about the environmental pollution?
It's inevitable that there will be ___________ in the workforce over the coming months.
I don't like to ask people for help as a rule but I wonder if you could ___________ me a favor.
I extend my sincere ___________ to the family and friends of John Miller, who has suddenly left us at the age of 54.
