currency book

2/4 Update - Hi All, just a quick note that I''''ve rewritten a fair bit of the chapters now to hopefully improve the pacing and flow of the chapters, plus address some of the other feedback received. Given a fair bit of change, I''''ll probably look to delete this and reupload it again as a new book. I''''ll leave this note up for a day and then kick off the delete and reupload, thanks all.