1. The problem statement, all variables and given/known data A potential difference Vab = 46.0 V is applied across the capacitor network of the following figure. If C1=C2=4.00μF and C4=8.00μF, what must the capacitance C3 be if the network is to store 2.80×10−3 J of electrical energy? 2. Relevant equations U=(1/2)CV^2 (1/C) = (1/c1) + (1/c2) + ... capacitors in series C = C1 + C2 + ... capacitors in parallel 3. The attempt at a solution U = (1/2)CV^2 2.80×10−3 = (1/2)C(46^2) C = 2.6 μF Capacitance of C1 and C2 = 1/(1/4 + 1/4) = 2 μF Total capacitance: 1/2.6 = 1/(2+C3) + 1/8 C3 = 1.85 μF I can't figure out why this answer is incorrect. Help much appreciated!