Content creation

Hello! If I have the same picture in different contents but it is uploaded each time in different folders(folders for different course presentations), how can I prevent searching engines from seeing copies/doubles of the same picture? How can I hide this copies from search engines or use the link to the same image instead of inserting the same picture for many times?

Hello,

Is there a way to delete a Comment in Course Presentation?  I accidentally created a comment and can't figure out how to remove it.  I can also envision someone making an inappropriate comment and wanting to remove it.

Thanks.