State the correct Feynman rules for diagrams describing
propagation between and scattering from 
-functions of strength
+A, giving expressions for all of the factors that appear in such
diagrams. Express your results terms of 1) k, 2) d,
the distance traveled between 
functions, and 3) the
parameter 
defined in (1).
Hint: You should be able to find these easily from your results
in (2).