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Two point charges, Q, =-7.1 JC and Q, = 13.8 JC , are placed at the corners of a rectangle as shown in the figure below. The side lengths of the rectangle are a = 3.7m and b= 7.1m. Determine the electric potential at the top-right corner of the rectangle. Take Coulomb's constant as k =9.0x 109 N . m2/C2. Express your answer in units of kV (kiloVolts) using two decimal places. Note that electric potential can be negative or positive. If your answer is negative, please do not forget the minus sign! Q1 a X Q2 b