The Water, Sanitation and Hygiene (WSH) program of the Gates Foundation was launched in mid-2005 as a "Learning Initiative," and became a full-fledged program under the Global Development Division in early 2010. The Foundation has since 2005 undertaken a wide range of efforts in the WASH sector involving research, experimentation, reflection, advocacy, and field implementation. In 2009, the Foundation decided to refocus its WASH effort mainly on sustainable sanitation services for the poor, using non-piped sanitation services (i.e. without the use of sewers), and less on water supply. This was because the sanitation sector was generally receiving less attention from other donors and from governments, and because the Foundation believed it had the potential to make a real difference through strategic investments.

Answer this question, if possible (if impossible, reply "unanswerable"): What efforts have the WSH taken
since 2005 undertaken a wide range of efforts in the WASH sector involving research, experimentation, reflection, advocacy, and field implementation