题目内容
听力原文： OK, in the last class we talked about the classification of trees and we ended up with-a basic description of angiosperm. You remember that those are plants with true flowers and seeds that develop into fruits. The common broadleaf trees we have on campus fall into this category. But our pines don't. Now ! hope you all followed my advice and wore comfortable shoes because as I said today we are going to do a little field study. To get started let me describe a couple of broadleaf trees we have in front of us. I'm sure you've all noticed that this big tree next to Brett Hall. It's a black walnut that must be 80 feet tall. As a matter of fact there is a plaque identifying. It is the tallest black walnut in the state. And from here we can see the beautiful archway of trees at the commons. They are American elms. The ones along the commons were planted when the college was founded 120 years ago. They have distinctive dark green leaves that look lopsided because the two sides of the leaf are unequal. I want you to notice the elm right outside the Jackson Hall. Some of the leaves have withered and turned yellow, maybe due to Dutch elm disease. Only a few branches seem affective so far but if this tree is sick it'll have to be cut down. Well, let's move on and I'll describe what we see as we go.
What are the students going to do during this class period？
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Banking panics may be prevented by means of______.
It is difficult to trace the history of certain ancient beads because they ______.
PART C
Directions: You will hear three dialogues or monologues. Before listening to each one, you will have 5 seconds to read each of the questions which accompany it. While listening, answer each question by choosing A, B, C or D. After listening, you will have 10 seconds to check your answer to each question. You will hear each piece ONLY ONCE.
听力原文： Karl Wilhelm Rontgen (1845—1923) astounded people with the first x-rays in 1895; this was followed three years later by the discovery of radium by Pierre and Marie Curie. But who were they？ In 1894, Marie and Pierre Curie met while studying in Paris. Their marriage on 25th July 1895 marked the start of a partnership which was to receive worldwide recognition.
The Curies discovered radium, a radioactive substance, in uranium oxide ore. They developed techniques for extracting it, but first did not fully understand its properties. Pierre Curie used to carry radium around in his waistcoat pocket and could not understand why he was developing a massive sore on his chest. This would have been fatal, but Pierre's life was cut short in 1906 when he was knocked down and killed by a horse and cart in the street. From then on, Marie devoted herself to completing the work that they had begun together.
Marie and Pierre Curie were awarded a joint Nobel Prize in 1904, followed up by a second one for Marie in 1911. Their research was crucial in the development of x-rays in surgery. During World War I Marie Curie helped to equip ambulances, which she drove to the front lines, with x-ray equipment. The International Red Cross made her head of its Radiological Service and she held training courses for medical orderlies and doctors in the new techniques.
Despite her success, Marie faced great opposition from male scientists in France and she never received the recognition she deserved. She died in 1934 from leukaemia, due to exposure to high-energy radiation used in her research. Radiation has since been used to treat cancer worldwide.
When were the first x-rays discovered？
Why does the author mention Continental Illinois Bank & Trusted Company of Chicago？
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