The graph of $f$ is shown in red, and the graph of $g$ is shown in blue. Use the graphs to evaluate each quantity given below.
NOTE: If only a blue section of graph shows up, that means the red graph is behind it.
NOTE: Write 'Does not exist' if the value does not exist.

a) $f(0) =$

b) $g(0) =$

c) $(fg)(0) =$

d) $f(0) - g(0) =$