Which permissions does the File Owner have in Chatter which a File Collaborator does not have?

Upon doing which operations on a file, does a user own a file in Chatter?

Which of these operations on a file in Chatter leads to the generation of a private file?

In Salesforce Mobile, a user profile like Custom – Recruiter can be assigned only one Mobile
Configuration at a time.

When loading a new account using Apex Data Loader and specifying the owner id to whom
the account should belong, under which of these cases, the data load will fail?
i. The owner id is an invalid id. There is no user in salesforce with this id
ii. The owner id belongs to an inactive user.

Under which of these cases the deletion of an account will fail?
i) The account has a related case
ii) The account has a related entitlement

What is the drawback of loading leads/cases using the Apex Data Loader as compared to
creating them from the UI?

User A belongs to profile ‘Custom – Recruiter’. At the profile level (Path as per Enhanced
Profile User Interface, Setup -> Manage Users -> Profiles -> Custom – Recruiter -> Objects
and Tabs -> Accounts) he does not have Read access on Account object. But yet he is able
to see, edit, delete account records. What could be the reason?

User A belongs to profile ‘Custom – Recruiter’. At the profile level (Path as per Enhanced
Profile User Interface, Setup -> Manage Users -> Profiles -> Custom – Recruiter -> Objects
and Tabs -> Accounts) he does not have Read access on Account object. But yet he is able
to view account records. He is not able to edit or delete account records. What could be the reason?

What is the Process Visualizer used for?