if you add up the durations from left to right on any level of a note tree you end up with a what?

Answer 1

Is the answer a whole note?
Here is a note tree.
https://www.google.com/search?q=note+tree&client=firefox-a&hs=9jr&rls=org.mozilla:en-US:official&channel=sb&tbm=isch&imgil=kxe2MvN9QkmVEM%253A%253B0n0Qqxw9S0aUrM%253Bhttp%25253A%25252F%25252Fwww.personal.kent.edu%25252F~jrex2%25252Fmusosaurus%25252Fzmeter.html&source=iu&pf=m&fir=kxe2MvN9QkmVEM%253A%252C0n0Qqxw9S0aUrM%252C_&usg=__UbPAYKTkCuutXAaSEszR78ejgfo%3D&biw=1007&bih=601&ved=0CCkQyjc&ei=MAASVLuONcLIggSJrYCoDQ#facrc=_&imgdii=_&imgrc=kxe2MvN9QkmVEM%253A%3B0n0Qqxw9S0aUrM%3Bhttp%253A%252F%252Fwww.personal.kent.edu%252F~jrex2%252Fmusosaurus%252Fimages%252Fnote_tree.jpg%3Bhttp%253A%252F%252Fwww.personal.kent.edu%252F~jrex2%252Fmusosaurus%252Fzmeter.html%3B367%3B193

Note that four quarter notes = 1 whole note (in time)
Eight eighth notes = 1 whole note (time)
etc.