Win 3 Points for Your House!

A ten-volume manuscript is stored in the correct order on a library shelf. Each volume is 4 1/2 inches thick, with 2 covers, each 1/2 inch thick. A worm, starting on page 1 of volume 1, eats its way in a straight line through the complete set and finishes on the last page of the last volume. What distance does it travel in it's journey?