Read the following article and select the best answer. Article: Today just as technology changed the face of industry, farmers have undergone an "agricultural revolution". On the farm of today, machines provide all the power. One of the most important benefits will be the farm computer. A few forward-looking farmers are already using computers to help them run their farms more efficiently. The computers help them keep more accurate records so they can make better decisions on what crops to plant, how much livestock to buy, when to sell their products, and how much profit they can expect. Many computer companies have been developing special computer programs just for farmers. Programs are being written for hog producers, grain farmers, potato farmers, and dairy farmers. In the future, farmers will be able to purchase computer programs made to their needs. Because of the growing importance of computers on the farm, students at agricultural colleges are required to take computer classes in addition to their normal agricultural courses. There can be no doubt that farmers will rely on computers even more in the future. While the old-time farm depended on horse power, and modern farms depend on machine power, farms of the future will depend on computer power. Another technological advance which is still in the experimental stage is the robot, a real "mechanized hired hand" that will be able to move and, in some ways, think like a human being. Unlike farmers of the present, farmers of the future will find that many day-to-day tasks will be done for them. Scientists are now developing robots that will be able to shear sheep, drive tractors, and harvest fruit. Even complex jobs will be done by robots. For example, in order to milk their cows, farmers must first drive them into the special barn , then connect them to the milking machines, watch the machines, and disconnect them when they are finished. In the future, this will all be done by robots. In addition, when the milking is completed, the robots will automatically check to make sure that the milk is pure. The complete... Question: Which sentence carries the main idea of the whole passage? - The first sentence of the first paragraph. - The first sentence of the second paragraph. - The first sentence of the third paragraph. - The last sentence of the second paragraph.
The first sentence of the first paragraph.

Read the following article and select the best answer. Article: Hiking is not only one of the best forms of physical exercise, but it is also one of the best forms of mental relaxation. It is good for all ages and especially good as a family and group activity. Since there are so many different kinds of hiking, it is not possible to give any general rules to follow. Short and frequent hikes, needing no planning or special equipment, are enjoyed by most people. *Keep in shape by walking at a fast pace for at least 15 minutes every day. Climbing stairs instead of using a lift and running not too far are also good ways of keeping in shape. *On any hike nothing is more important than good, comfortable shoes. *The things you take might include matches in a waterproof box, a knife, compass, map first aid items and flashlight. *Cameras may be taken, but don't load with too much. *On longer hikes keep a comfortable, steady pace and take rest stops often. *Drink only safe water. If in doubt, boil the water. *Don't go along the busy roads. When you have to use a road, keep as far over on the left as possible. *Leave word at home or some other place as to where you are going and when you plan to return. *On almost any hike, a map is a good idea. If going into a strange place, a detailed map is most useful. *Take along a field guide on flowers, birds, rocks, or other subjects depending upon your interests. This can add greatly to the enjoyment and educational value of your hike. Question: The author mostly talks about _ . - general rules for hiking in mountainous areas - steps to be taken against dangerous animals - general things that should be paid attention to in hiking - all the things that are needed in hiking
general things that should be paid attention to in hiking

Read the following article and select the best answer. Article: Scientists at Harvard University and Bates College find female chimpanzees appear to treat sticks as dolls, carrying them around until they have children of their own. Young males engage in such behavior much less frequently. The new work by Sonya M. Kahlenberg and Richard W. Wrangham, described this week in the journal Current Biology, provides the first evidence of a wild nonhuman species playing with dolls, as well as the first known sex difference in a wild animal's choice of playthings. The two researchers say their work adds to a growing body of evidence that human children are probably born with their own ideas of how they want to behave, rather than simply mirroring other girls who play with dolls and boys who play with trucks. Doll play among humans could have its origins in object--carrying by earlier apes , they say, suggesting that toy selection is probably not due entirely to socialization. "In humans, there are obvious sex differences in children's toy play, and these are remarkably similar across cultures," says Kahlenberg. "While socialization by elders and peers has been the primary explanation, our work suggests that biology may also have an important role to play in activity preferences." In 14 years of data on chimpanzee behavior at the Kibale National Park in Uganda, Kahlenberg and Wrangham counted more than 100 examples of stickcarrying. Some young chimpanzees carried sticks into the nest to sleep with them and on one occasion built a separate nest for the stick. "We have seen juveniles occasionally carrying sticks for many years, and because they sometimes treated them rather like dolls, we wanted to know if in general this behavior tended to represent something like playing with dolls," says Wrangham, a Professor at Harvard. "If the doll hypothesis was right, we thought that females should carry sticks more than males do, and that the chimpanzees should stop carrying sticks when they had their first child. We have now watched enough young chimpanzees to prove both points." Question: It can be concluded from the passage that _ . - both humans and chimpanzees choose their playthings due to sex difference - different factors cause humans and chimpanzees to choose different playthings - only female chimpanzees have playthings - chimpanzees usually choose playthings for their children
both humans and chimpanzees choose their playthings due to sex difference