The bill in this context is a theatrical poster/leaflet describing the acts to be presented. If the bill had too few acts, more acts would be sought to 'fill the bill'. This expression appears to have originated in the USA in the 19th Century. The expression can also sometimes be used when a particular act or event takes up the entire show (or at least dominates).
Note: Although when I set this particular week's quiz I had in mind 'Fill the Bill', F T Bill could also translate as 'Foot The Bill' - meaning to pay the bill - e.g. two people in a restaurant with one offering to foot the bill for the other. All three options - fit the bill, fill the bill and foot the bill were all considered correct when selecting this week's winner.
U.S. ebook sales up in 2012, but rate of growth is slowing(May 16 2013) In 2012, trade book sales (i.e. non academic book sales) rose 6.9%, to $15.049 billion, and e-book sales continued to grow, although the rate of growth...