Questions 56 to 60 are based on the following passage: 　　Joe Bloggs worked in a large and famous company. The president of the company believed in keeping his employees (雇员) happy. One year，he offered them a pension (养老金) fund. The idea was that the workers would pay five percent of their wages into a pension fund. The company would also pay a sum equal to five percent. When an employee retired from the company，he could take with him all the money that he and the company had put into his pension fund. 　　“I will open the pension fund, ”the president of the company said, “as soon as you all agree to join. Unless you all join, I won’t open the fund. You’ve got a week to make up your minds. 　　The idea was a very good one and everyone except Joe Bloggs agreed to join. 　　“I don’t understand it,” Bloggs said. 　　His co-workers tried to explain it to him, but he just kept saying, “I still don’t understand it.” 　　Time passed and when there was only an hour left before the week was up, the president sent for Joe Bloggs to come to his office on the 20th floor. 　　“Mr. Bloggs,” he said, “all the employees agree with what I am going to say to you. So listen carefully.” 　　“It had better be good.”Bloggs said. 　　“Oh, it is,” the president said. “If you don’t agree to join the pension fund before I finish counting to ten, the security guards will throw you out of the window. 　　Joe Bloggs immediately signed the form which said he would agree to join the plan. 　　“Now that you have explained it clearly”, he said, “of course I’ll join.” The president gave his employees one week to decide whether to join the　　pension fund or not.