On one Linux (such as Ubuntu) machine that uses discretionary access control, consider the following case: Alice, Bob, Charlie, and Dave are four users. Alice owns a file treasure.tat and she needs to set the file permissions on treasure.tat to meet the following requirements. 1. There must be only a single copy of this file in the whole system. In other words, Alice must not, even if she is capable of, make a physical copy of file treasure.txt. 2. Alice's own permissions on the file must be readable/writableon-executable. 3. Alice needs to allow Bob to read and write this file 4. Alice needs to allow Charlie to read but rtot write the file. 5. The execute permission of treasure.txt must be disabled for all users. 6. All other users (such as Dave) in the system must not be able to read or write the file. 7. Alice does not have sudo privilege on this machine. But if necessary, she can ask the systems administrator to create groups for her. She may also ask the systems administrator to install software to the machine and may even ask for sudo privileges from the systems administrator, if necessary. How can Alice meet the above requirements? In your solution, in addition to the description, you must also provide the exact Linux commands. You must ru actually work. No working commands, no points. n your commands on your Linux box to make sure that they