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I am level 10 in Pokemon GO and I caught two of the same Pokemon very recently, both of which can be evolved three times.
One Pokemon has a CP of 210 with a moveset of power (10,15). I also have another of the same Pokemon with CP 140 with a moveset of power (10,25).
I need to decide what to evolve. Some people tell me go with CP and the others tell me look at the "bar" (which I do not understand how I can derive implications on what to derive by looking at the Bar above the Pokemon's head because the bar is same for all of that type of pokemon except it is further down for the one with higher CP). Moreover, others tell me I need to evolve both first to see which one is better.
What should one consider before evolving and when should I use the power up button?