Finding (f o g)(2), (g o f)(2), etc. Calculus homework help

 Let f be the linear function (in blue) and let g be the parabolic function (in red) below.

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1. (f o g)( 2 ) = 

2. (g o f)( 2 ) = 

3. (f o f)( 2 ) = 

4. (g o g)( 2 ) = 

5. (f + g)( 4 ) = 

6. (f / g)( 2 ) = 

I am having trouble understanding compositions and finding the correct function from the graph.