单项选择题 User2 is complaining that he is unable to list the contents of a directory. What is the most likely cause?（）

单项选择题 After making changes to the profile for an LPAR, the administrator asks the operator to bring the LPAR back up into a running state with the new changes. Which of the following is the correct way to do this?（）

单项选择题 Which of the following can be used to insert a new line below the current line inside a vi session?（）