The publishers have worked hard to preserve all the content from the physical version to be used in the digital version. That means you'll see the same graphs, charts, tables, drawings, etc. as you normally would in the physical version.
ePub: The ePub books do not maintain the layout that a traditional bound book has, because the text is reflowable the font size can be easily adjusted no matter what the size of the screen.
Pdf: The Page-Fidelity version of an eTextbook maintains the look at feel of a bound book, its text is fixed the screen size regulates the size of the text.