Convert PDF or other format to PDF/A

Hello,

I have some questions about converting to PDF/A using Adobe Acrobat 9 Pro

• I want to know if it is possible to convert PDF-documents or other 'image-documents' to PDF/A.
  Via advanced - Prefligt you can convert separate PDF-documents into PDF/A-documents. I can't  find the possibility to convert more documents in one go. For example a whole file/folder.
  
  
• And is it possible to convert several (more than one, a whole file/folder) 'image-documents' at one go into PDF/A-files. And if this is possible what kind of 'image-document'/format has it to be. For example jpeg or other.

• And at last: is there a quick way to convert a single 'image-document' into PDF/A. And if this is possible what kind of 'image-document'/format has it to be. For example jpeg or other.

I hope to receive some helpfull reactions for which I thank you beforehand.

Greetings,

Anke