Consider the graphs of $y = f(x)$ and $y = g(x)$ sketch in blue and red respectively on the graph below:

For each function, enter the letter of the graph A - F which represents it. Clearly not all of the graphs are matched with one of the equations.

$f(x) + g(x)$
$f(x) - g(x)$
$g(x) - f(x)$