20.
Which security features were changed or added to the upgraded banknotes comparing with the previous issues?

All security features were changed and improved, namely: vertical security thread, watermark,latent image, hologram, see-through, optical variable ink (OVI), blindmark, intaglio, iridescent stripe, microletterings, UV fluorescent and phosphorescent properties. Added: optical variable magnetic ink (SPARK), magnetic intaglio, infrared intaglio.