题目

每年4月23日是“世界读书日”，为了了解某校八年级500名学生对“世界读书日”的知晓情况，从中随机抽取了50名学生进行调查．在这次调查中，样本是（ ） A．  500名学生 B．  所抽取的50名学生对“世界读书日”的知晓情况 C．  50名学生 D．  每一名学生对“世界读书日”的知晓情况 答案：B             解：样本是所抽取的50名学生对“世界读书日”的知晓情况．阅读理解     What do you know about the sea? You may have seen it. Some of us have swum or bathed in it. It looks beautiful on a fine sunny day and it can be very rough when there is a strong wind. What other things do we do about it? Of course, the sea is very large. In the world there is more sea than land. Thesea covers three quarters of the earth. The sea is also very deep in some places. It is not deep everywhere; some parts of it are very great. At one spot, near Japan the sea is nearly 11kilometres deep just think of it, the highest mountain in the world is only 9 kilometres high! If you have swum in the sea, you know that the water is salty. Rivers carry salt from the land into the sea. Some parts of the sea are more salty than other parts. Do you know the Dead Sea in Arabia? It is very salty. Swimmers cannot sink in it! Fish cannot live in the Dead Sea. It is a strange sea. In most parts of the sea, there are a lot of fishes and plants. Some live near the top of the sea. Others live deep down. No sunlight can reach the depth of the sea. So it is completely dark. Strange fishes live there. Some are blind. Some have their ownlights. Some have great jaws（嘴巴）.With their great jaws, they swallow fish larger than themselves. The sea can be very cold. Deep sea divers know this well. At the top the water may be warm. Then as the divers go down, the sea becomes colder and colder.     Many scientists are now making a study of animal and plant life in the sea. They hope to find newresources for mankind.1. Which of the following statements is NOT true?   A. Land covers one fourth of the area of the earth. B. The depths of the sea are different in different places.C. The depth of a sea at one spot near Japan is nearly the height of the highest mountain. D. The salt in the sea mainly comes from the land. 2. The Dead Sea is lifeless because A. the water in it is too coldB. the water in it is too salty for anything to grow C. the water in it never flowsD. no sunlight can reach the bottom of the sea3. We can see the underlined word "rough" in this passage means "       "  A. ugly                        B. noisyC. cold                        D. not calm4. What does the writer intend to tell us in the last paragraph ?      A. The necessity (必要性) of the study of the sea.B. The purpose of man's further study of the sea.C. Man's limited knowledge of the sea.D. The importance of new resources for man.