Answer
a.
Shift the graph of f(x,y) in the +x direction by 2 units.
b.
Shift the graph of f(x,y) in the -y direction by 2 units.
c.
Shift the graph of f(x,y) in the -x direction by 3 units, and then shift in the +y direction by 4 units.
Work Step by Step
Analogy with 2D graphs where
$f(x-c)$ meant shifting to the right (the +x direction) by c units,
$f(x+c)$ meant shifting to the left (the -x direction) by c units,
