A power chord, like I said earlier, is made up of the "root(I)" and the "fifth(V)". It is important to know this so that you can construct "more uncommon" and "personalized" power chord shapes.
The common power chord is a very simple chord to make, take the "E" major scale(E, F#, G#, A, B, C#, D#, and E again if you count the "octave".) Now take the Root, "E", and play it with the fifth note from the root, "B", and you have a power chord. This works for all major scales and all over the fretboard. Now, Knowing this consept, you can make chords like the one in figure B1.
Can you figure out what chord this is? Look at the individual notes....