tailieunhanh - What do you think of the opinion polls?

Tham khảo tài liệu 'what do you think of the opinion polls?', ngoại ngữ, kỹ năng viết tiếng anh phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | What do you think of the opinion polls People often laugh at opinion polls and remember times when they were slightly incorrect. However they often forget all the time when they were accurate. A poll should be conducted very carefully and should sample a crosssection of the population. The cross-section should be selected very carefully so that the right balance of ages sexes and social classes can be achieved. At first it was very difficult for many people to accept that a sample of one or two thousand could reflect accurately the views of millions but polls have now proved themselves. However polls should not claim to do what they are not intended to do. The findings should always be examined very carefully before predictions are made with any degree of certainty. How should people protect and preserve the natural resources Conservation concerns men s safeguarding and preservation of natural resources and his responsibility for improving the environmental conditions in which he lives. An important task of conservation is the prevention of waste - waste of forests soil minerals wildlife and human life. Trees help to preserve land because their roots bind the soil and retain water. Without trees heavy rains will cause soil erosion and the remaining land becomes poor and worthless. Terrible floods often occur in the areas where trees are cut down in great quantity. Forest conservation also means the prevention of bush fires and the .