Set up a triple integral to find the mass of the solid tetrahedron bounded by the xy-plane, the yz-plane, the xz-plane, and the plane $x/3 + y/2 + z/6 = 1$, if the density function is given by $\delta(x,y,z) = x + y$. Write an iterated integral in the form below to find the mass of the solid.

$\displaystyle \iiint\limits_R f(x,y,z) \, dV = \int_A^B \!\! \int_C^D \!\! \int_E^F$ $\, dz \, dy \, dx$
with limits of integration

A =
B =
C =
D =
E =
F =