...
- select "Create an image PDF of the current chapter" and choose the chapter in the dropdown box, or
- select "Create an image PDF of pages ___ _ to _ ___" and enter the page numbers.
NOTE: the page numbers you use here should be those that appear in the upper right hand corner of your screen, NOT the printed page numbers inside the book!
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To remove a book from your bookshelf, click on the Trashcan 
icon next to it in your bookshelf and click the OK button in the window that comes up.
Marking/Highlighting/Commenting on a
...
Book
Want to mark a particular quote or portion of a book? Use your cursor to mark the section, then click on the Highlight button 
at the top of the page. The text will appear highlighted in yellow.