Directions: Read the following passage. Answer the questions according to the information given in the passage and the required words limit. Write your answers on your answer sheet.

Facts are sometimes more unusual than fiction. The following case makes Agatha Christie’s plot look like children’s literature.

The medical inspection of Ronald Opus’s body showed that he died from a shot gun wound of the head. He had jumped from the top of a ten-storey building intending to commit suicide(自杀). As he fell past the ninth floor, a shotgun blast through a window killed him immediately. Neither the shooter nor Opus knew that a safety net had been put up at the eighth floor level to protect some window washers and that Opus would not have been able to complete his suicide anyway because of this.

       In the room on the ninth floor where the shotgun blast went through  an elderly man and his wife were arguing and he was threatening her with the shotgun. He was so upset that when he pulled the trigger（扳机）, he completely missed his wife and the pellets（小子弹） went through the window, striking the falling Opus.

       The old man said it was his long-term habit to threaten his wife with the unloaded shotgun. He had no intention to murder her. Therefore, the killing of Opus seemed to be an accident. That is, the gun had been accidentally loaded.

       The continuing investigation(调查) turned up a witness who saw the old couple’s son loading the shotgun six weeks before the fatal incident. It turned out that the old lady had cut off his son’s financial(经济的) support and the son, knowing the habit of his father to use the shotgun threateningly against his mother, loaded the gun with the expectation that his father would shoot his mother.

       Further investigation showed that the son had become increasingly depressed over the failure of his attempt to engineer(密谋策划) his mother’s murder. This led him to jump off the ten-storey building, only to be killed by a shotgun blast through a ninth floor window.

       The case was closed as a suicide.

1.Who shot Ronald Opus? （no more than 2 words）

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2.Who loaded the old man’s shotgun? （no more than 2 words）

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3.What was the safety net put up at the eighth floor used for? （no more than 8 words）

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4.What was the old man’s long-term habit? （no more than 8 words）

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