Potential Energy: In the figure, +4.0-?C and -4.0-?C point charges are located as shown. Now an additional +2.00-µC point charge is placed at point A. What is the electric potential energy of this system of three charges, relative to infinity? (k = 1/4??0 = 8.99 × 109 N ? m2/C2) 
A. +264 mJ
B. -264 mJ
C. 0.00 J
D. -26.4 mJ
E. +26.4 mJ
Answer: B
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