Final answer:
An enclosure notation on a block style business letter indicates any additional items that are included with the letter.
Step-by-step explanation:
An enclosure notation on a block style business letter indicates any additional items that are included with the letter. It is typically placed one line below the typed name and serves as a way to inform the recipient that there are additional documents or materials included with the letter. These enclosures can range from resumes to writing samples or any other relevant supporting documents.