Directions: In this section, there is one passage followed by 6 statements. Go over the passage quickly. For questions 66-71, mark T (/for True) if the statement agrees with the information given in the passage; F (for False) if the statement contradicts with information given in the passage; NG (for Not Given) if the information is not given in the passage.Questions 66-71 are based on the following passage. Heat loss by sweating depends on the fact that when a liquid evaporates, it absorbs an enormous quantity of heat from its surroundings. Therefore, when 1 ml. of sweat evaporate, a great deal of heat is absorbed from the surface of the body in contact with it. This heat transfer occurs even if the environment is hotter than the body. Two factors affect the rate of evaporation of sweat, and therefore the effectiveness of sweating as a method of cooling the body. The first is the amount of movement of air surrounding the body. The second is the amount of water vapor in the air that surrounds the body. When air moves over the surface of water, the amount of evaporation is greatly increased. For this reason, sweat evaporates very rapidly on windy days, and the rate of heat loss by sweating is much more than on a still day. This accounts for the fact that hot still days are much less comfortable than hot windy days. In contrast, the sweat evaporates very rapidly on hot windy days, and cools the body quickly and effectively. The second factor is the amount of water vapor in the air--the humidity. When air is carrying the maximum amount of water vapor that it can hold, it is said to be 100% saturated with water vapor. The relative humidity of the air is said to be 100%. Under these conditions the air cannot carry any water, so no water can evaporate. When the relative humidity is high, therefore, sweat cannot evaporate. Instead, it forms large drops and runs off your skin without cooling you. When the air is very dry and carries no water at all, the relative humidity is said to be 0%. It is obvious that under these conditions, evaporation will be much more rapid. Therefore, sweating will be much more effective as a method of losing heat from the body. On a hot dry day, sweat evaporates as soon as it is formed, and you feel reasonably cool even though the temperature of your environment is very high. ______ The heat transfer happens on the condition that the environment is cooler than the body.
Directions: In this section, there is one passage followed by 5 questions. Read the passage carefully, then answer the questions in a maximum of 10 words. Questions 61-65 are based on the following passage.Centuries ago, man discovered that removing moisture from food helps to preserve it, and that the easiest way to do this is to expose the food to sun and wind. Fruit is sun-dried in Asia Minor, Greece, Spain and other Mediterranean countries, and also in California, South Africa and Australia. The methods used vary, but in general, the fruit is spread out on trays in drying yards in the hot sun. In order to prevent darkening, pears, peaches and apricots are exposed to the fumes of burning sulphur before drying. Plums for making prunes, and certain varieties of grapes for making raisins and currants, are dipped in an alkaline solution in order to crack the skins the fruit slightly and remove their wax coating, so increasing the rate of drying. Nowadays most foods are dried mechanically. The conventional method of such dehydration is to put food in chambers through which hot hair is blown at temperatures of about 110℃ at entry to about 43℃ at exit. This is the usual method for drying such things as vegetables, minced meat, and fish. Liquids Such as milk, coffee, tea, soups and eggs may be dried by pouring them over a heated horizontal steel cylinder or by spraying them into a chamber through which a current of hot air passes. In the first case, the dried material is scraped off the roller as a thin film which is then broken up into small, though still relatively coarse flakes. In the second process it falls to the bottom of the chamber as a fine powder. Where recognizable pieces of meat and vegetables are required, as in soup, the ingredients are dried separately and then mixed. Dried foods take up less room and weigh less than the same food packed in cans or frozen, and they do not need to be stored in special conditions. For these reasons they are invaluable to climbers, explorers and soldiers in battle, who have little storage space. They are also popular with housewives because it takes so little time to cook them. Usually it is just a case of replacing the dried-out moisture with boiling water. Why do housewives like dried foods
膳食纤维的主要生理意义是
A. 降低血中三酰甘油
B. 吸收后提供人体微量元素
C. 提供人体维生素
D. 防止便秘,降低血胆固醇
E. 促进食物的消化吸收
Since the island has been barren for so many years, the natives must now ______ much of their food.
A. deliver
B. utilize
C. produce
D. import