Answer:
The graph of y=f(x) will shift up 20 units.
Step-by-step explanation:
If we have a function h(x) = g(x) + c
Where c is a constant. We can say that h(x) is g(x) shifted c units up
Then, if the new graph is y = f(x) + 20, we can said that it is the graph of y = f(x) shifted 20 units up.