2017 Q.2 ATO

[steak]

Please review my attempt at the 2017 Q.2 ATO question. The second part of the question requires a bit more I think to get some more marks. Probably a bit more of an explanation explaining the diagram. This is actually my 3rd attempt at this question. This style of answer seems, to me anyway, the way easiest way to answer it.
I will probably have a revisit.

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