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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.

A large number of inventions require years of arduous research and development before they are perfected. For instance, Thomas Edison had to make more than 1,000 attempts to invent the incandescent light bulb before he finally succeeded. History is replete with numerous other examples of people trying, yet failing to make inventions before they eventually succeeded. Yet some inventions have come about not through hard work but simply by accident.

In most cases, when someone unintentionally invented something, the inventor was attempting to create something else. For example, in the 1930s, chemist Roy Plunkett was attempting to make a new substance that could be used to refrigerate items. He mixed some chemicals together. Then, he put them into a pressurized container and cooled the mixture. By the time his experiment was complete, he had a new invention. It was not a new substance that could be used for refrigeration though. Instead, he had invented Teflon, which is today most commonly used to make nonstick pots and pans. Similarly, decades earlier, John Pemberton was a pharmacist in Atlanta, Georgia. He was attempting to create a tonic that people could use whenever they had headaches. While he was not successful in that endeavor, he managed to invent Coca – Cola, the world – famous carbonated soft drink.

Scientists have also made crucial discoveries by accident when they were conducting experiments. In 1928, Alexander Fleming discovered penicillin, an antibiotic, in this manner. He discovered some mold growing in a dish with some bacteria. He noticed that the bacteria seemed to be avoiding the mold. When he investigated further, he determined some of the many useful properties of penicillin, which has saved millions of lives over the past few decades. Likewise, in 1946, scientist Percy Spencer was conducting an experiment with microwaves. He had a candy bar in his pocket, and he noticed that it suddenly melted. He investigated and learned the reason why that had happened. Soon afterward, he built a device that could utilize microwaves to heat food. the microwave oven.

What does the author imply about penicillin?

A. It is an invaluable medical supply.

B. Mold combines with bacteria to make it. 

C. Some people are not affected by it.

D. Doctors seldom use it nowadays.

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 following questions.

Most people think that lions only come from Africa. This is understandable because in fact most lions do come from there but this has not always been the case. If we went back ten thousand years. we would find that there were lions roaming vast sections of the globe. However now, unfortunately only a very small section of the lion’s former habitat remains.

Asiatic lions are sub-species of African lions. It is almost a hundred thousand years since the Asiatic lions split off and developed as a sub-species. At one time the Asiatic lion was living as far west as Greece and they were found from there, but in a band that spreads east through various countries of the Middle East, all the way to India. In museums now, you can see Greek coins that have clear images of the Asiatic lion on them. Most of them are dated at around 500 B.C.

However, Europe saw its last Asiatic lions roaming free to thousand years ago. Over the next nineteen hundred years the numbers of Asiatic lions in the other areas declined steadily, but it was only in the nineteenth century that they disappeared from everywhere but in India. The Gir Wildlife Sanctuary in India was established especially to protect the Asiatic lion. There are now around three hundred Asiatic lions in India and almost all of them are in this sanctuary. However, despite living in a sanctuary, which makes them safe from hunters, they still face a number of problems that threaten their survival. One of these is the ever-present danger of disease. This is what killed more than a third of Africa’s Serengeti lions in 1994, and people are fearful that something similar could happen in the Gir Sanctuary and kill off many of the Asiatic lions there. India’s lions are particular vulnerable because they have a limited gene pool. The reason for this is interesting – it is because all of them are descended from a few dozen lions that were saved by a prince who took a particular interest in them. He was very healthy, and he managed to protect them otherwise they would probably have died out completely.

When you see the Asiatic lion in India, what you sense is enormous vitality. They are very impressive animals and you would never guess that they this vulnerability when you look at them.

The phrase “split off” in the second paragraph is closest in meaning to___.

A. spotted animals 

B. divided

C. developed into different species

D. changed the original species