Which of the following statements is TRUE, according to the passage?
C. S-process and r-process are the predominant mechanisms for the production of heavy elements.
D. Researchers focused on the light elements when observe the crash’s aftermath.
Đáp án B
Phát biểu nào sau đây là đúng, theo đoạn văn?
A. Vàng rơi xuống từ bầu trời như nước mắt hoặc mồ hôi của thần mặt trời Inti
B. Các nhà khoa học không thể xác định chính xác các nguyên tố trong một hỗn hợp các kết quả
C. Quá trình S và quá trình R là các cơ chế chiếm ưu thế để sản xuất các nguyên tố nặng
D. Các nhà nghiên cứu tập trung vào các yếu tố ánh sáng khi quan sát hậu quả của vụ tai nạn
Căn cứ vào thông tin đoạn đầu:
Astronomers have for the first time definitively ID'd the birth of a specific heavy element during a neutron-star smashup. (Các nhà thiên văn học lần đầu tiên xác định một cách rõ ràng sự ra đời của một nguyên tố nặng cụ thể trong một vụ va chạm sao neutron.)
*Note: ID'd = Identificated
=> Việc xác định được rõ ràng danh tính của các nguyên tố mới chỉ được thực hiện trong thời gian gần đây vì tác giả đang dùng thì hiện tại hoàn thành. Chứng tỏ, điều này trong quá khứ là chưa thể làm được. Chọn đáp án B, dùng "couldn't Vo" để diễn tả một hành động không có khả năng làm được trong quá khứ.
Some studies have suggested a link between certain types of __________ sweetener and cancer.
Mark the letter A, B, C, or D to indicate the sentence that is closest in meaning to each of the following questions.
"Your application must be submitted before the end of the month," said the secretary to applicants.
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
Astronomers have for the first time definitively ID’d the birth of a specific heavy element during a neutron-star smashup. They found strontium. And it showed up in the wavelengths of light — or spectra — making up this collision’s afterglow.
Scientists had assumed that a collision by two super-dense objects, such as neutron stars, would trigger a chain of nuclear reactions. They’re known as the r-process. In such an environment, the nuclei of atoms could rapidly gobble up neutrons. Afterward, those nuclei would become transformed in a process known as radioactive decay. The r-process was seen as a way to transform old, smaller elements into newer, bigger ones. About half of all elements heavier than iron were thought to be made in the r-process. Finding strontium in the recent collision at last offered the most direct evidence yet that neutron-star collisions really do trigger the r-process.
Physicists had long predicted that silver, gold and many other elements more massive than iron formed this way. But scientists weren’t sure where those r-process reactions took place. After all, no one had directly seen the r-process underway in a celestial event. Or they didn’t until the merger of two neutron stars in 2017. Scientists quickly analyzed light given off by that cataclysm. In it, they found evidence of the birth of a hodgepodge of heavy elements. All would seem to have come from the r-process.
The researchers were examining mostly very heavy elements — ones whose complex atomic structures can generate millions of spectral features. And all of those features were not yet fully known, Watson points out. This made it extremely difficult to tease apart which elements were present, he says.
Strontium, however, is relatively light compared to other r-process elements. And its simple atomic structure creates a few strong and well-known spectral clues. So Watson and his colleagues expanded their analysis to consider it. In doing so, they turned up the clear "fingerprint" of strontium. It emerged in light collected by the Very Large Telescope in Chile within a few days of the neutron-star collision. Seeing strontium in the afterglow wasn’t all that unexpected, says Brian Metzger. He’s an astrophysicist at Columbia University in New York City and not involved in the new work. Strontium, he notes, “does tell us something interesting” about the elements formed during the neutron-star collision.
(Source: https://www.sciencenewsforstudents.org/)
Which best serves as the title for the passage?
Mark the letter A, B, C or D to indicate the correct answer to each of the following questions.
Jane's eyes burned and her shoulders ached. She _______ at the computer for five straight hours. Finally, she took a break.
Mark the letter A, B, C, or D to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.
A: "Are you attending the conference on gender equality this week?"
B: “___________________”
Mark the letter A, B, C, or D to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions.
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
Bali, the fabled "Island of the Gods", has been enchanting visitors for centuries with its rich cultural traditions and spectacular panoramas. From lofty, mist enshrouded volcanoes and cool mountain lakes down through terraced rice fields to a golden strand lapped by azure waters, every square inch of Bali offers a fresh and unforgettable image.
No less enchanting are its people, some 2.7 million souls whose artistry and piety are recognized throughout the world Balinese Hinduism, a complex fusion of Indian cosmology. Tantric Buddhism and homegrown mythology, is the primary faith of Bali's inhabitants, and so deeply woven into the fabric of their daily lives that the line between the spiritual and the material is blurry at best.
Those of you keen on delving into the island's fascinating culture will have plenty of opportunities, as colorful ceremonies and traditional performances occur with regularity of sunrise. Most hotels offer nightly dance shows of one form or another, tailored to tourist audiences but none the less exquisite. The hill town of Ubud, the island's premier arts center, also has a full schedule of performance, and the nearby stone-cutter's village of Batubulan is famed for its Barong lion dances. The shoppers among you will find Bali a treasure house of handicrafts and fine works of art. The Balinese are incredibly gifted artists and craftsmen, and their material creations are imbued with the same sense of wonderment with which they regard their universe. Stone and wood carvings, traditional and modern paintings and intricately designed jewelry in gold and silver are readily in shops and galleries throughout the island.
As for recreation, there is no shortage of option. Nature walks, horseback riding, diving, surfing, even bungy jumping, and white water rafting await the adventurous here.
(Source: https://books.google.com.vn/books)
The topic of the given passage is ____________.
An 18-year-old girl, of no fixed _____, was charged with robbery in connection with the incident.
You can find all these recreational activities in Bali EXCEPT ____.