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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 from 36 to 42.

People have been donating blood since the early twentieth century to help accident victims and patients undergoing surgical procedures. Usually a pint of whole blood is donated, and it is then divided into platelets, white blood cells, and red blood cells. People can donate blood (for red blood cells] about once every two months. Transfusing the blood from the donor to the recipient is straightforward. It involves taking the blood from a donor's arm vein by means of a hypodermic syringe. The blood flows through a plastic tube to a collection bag or bottle that contains sodium citrate, which prevents the blood from clotting. When the blood is given to a patient, a plastic tube and hypodermic needle are connected to the recipient's arm. The blood flows down from the container by gravity. This is a slow process and may last as long as 2 hours to complete the infusion of blood into the recipient. The patient is protected from being infected during the transfusion. Only sterile containers, tubing, and needles are used, and this helps ensure that transfused or stored blood is not exposed to disease causing bacteria. Negative reactions to transfusions are not unusual. The recipient may suffer an allergic reaction or be sensitive to donor leukocytes. Some may suffer from an undetected red cell incompatibility. Unexplained reactions are also fairly common, Although they are rare, other causes of such negative reactions include contaminated blood, air bubbles in the blood, overloading of the circulatory system through administration of excess blood, or sensitivity to donor plasma or platelets. Today, hospitals and blood banks go to great lengths to screen all blood donors and their blood. All donated blood is routinely and rigorously tested for diseases, such as HIV, hepatitis B, and syphilis. When the recipient is a newborn or an infant, the blood is usually irradiated to eliminate harmful elements. Donated blood is washed, and the white blood cells and platelets removed. Storing the blood sometimes requires a freezing process. To freeze the red blood cells, a glycerol solution is added. To unfreeze, the glycerolis removed. The ability to store blood for long periods has been a boon to human health.

Question 40: What can the phrase "go to great length" best replaced by?

A. irradiate

B. test rigorously

C. monitor routinely

D. removed

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 from 35 to 42.

   It is hard to think of a world without gas or electricity. Both are commonly used for lighting and heating today. We now can instantly flick a lighter or strike a match to make a flame. But it was not long ago that there were no such things as matches or lighters. To make fire, it was necessary to strike a piece of iron on flint for sparks to ignite some tinder. If the tinder was damp, or the flint old, you had to borrow some fire from a neighbor.

   We do not know exactly when or how people first used fire. Perhaps, many ages ago, they found that sticks would bum if they were dropped into some hole where melted lava from a volcano lay boiling. They brought the lighted sticks back to make their fire in a cave. Or, they may have seen trees catch fire through being struck by lightning, and used the trees to start their own fires.

   Gradually people learned they could start a fire without traveling far to find flames. They rubbed two pieces of wood together. This method was used for thousands of years.

   When people became used to making fires with which to cook food and stay warm at night, they found that certain resins or gums from trees burnt longer and brighter. They melted resins and dipped branches in the liquid to make torches that lit their homes at night. Iron stands in which torches used to be fixed can still be seen in old buildings of Europe.

   There was no lighting in city streets until gas lamps, and then electric lamps were installed. Boys ran about London at night carrying torches of burning material. They were called torch boys, or link boys, and earned a living by guiding visitors to friends’ houses at night.

   For centuries homes were lit by candles until oil was found. Even then, oil lamps were no more effective than a cluster of candles. We read about the splendors and marvels of ancient palaces and castles, but we forget that they must have been gloomy and murky places at night.

What form of street lighting was used in London when link boys used to work there?

A. Gas lighting

B. No lighting at all

C. Electric lighting. 

D. Oil lighting