How do I get the U_E = the equation on the right to equal the - 0.035 J? I can't get the bottom calculations to the final answer. What does the x 10^-12 C²/m come from? This is on the last line. To help: q1 is 2.0?C q2 is 2.0?C q3 is -3.0?C. (I don't know why the micro symbol is elevated.)

17.1 ELECTRIC POTENTIAL ENERGY To find the potential energy due to more than two point charges, we add the potential energies of each pair of charges. For three point charges, there are three pairs, so the potential energy is C C C C C C UEzk 1,.!/3+ 1,113+ 1,?\" [2 I3 23 The potential energy is the negative of the work done by the electric field as the three charges are put into their positions, starting from infinite separation . \f