Multiple ways of performing a simple calculation in JMP Software.

I have results from an experiment. It is an investigation of a material that can reasonably be expected to obey Ohm's Law.
If you want to take a look at the data yourself, you can find them here:
www.pega-analytics.co.uk/blog...
Based on the results of this experiment, what is the resistance? It's a simple calculation - but you will get different answers depending on how you approach the problem!

[@user-fj4zo1ql7h]

how can choose the calculation(simulation)ways will influence the simulation result, so that means must base on the actually status and the experience to choose the perfect mode to simulation, right?