With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: A lending library was open on 9 May 2013 in a special area by Gate 1. All books were donated by public including Estonian president Toomas Hendrik Ilves and the First Lady of Estonia Evelin Ilves. The library will have books in ten different languages, the majority being in Estonian, Russian and English. There will also be a selection of children's books. On 16 August 2013 Tallinn Airport unveiled a gallery and started exhibiting artists' work in the Passenger Terminal. The gallery of rotating exhibitions on the 1st floor of the Passenger Terminal is open to all arriving and departing passengers as well as those seeing them off or meeting them.
text_B: Was the gallery in the Passenger Terminal open before August 16, 2013?
NO.