Four 20-µC Point Are at the Corners of a Rectangle with with Sides

Multiple Choice

Four 2.0-µC point are at the corners of a rectangle with sides of length 3.0 cm and 4.0 cm.What is the electric potential (relative to infinity) at the midpoint of the rectangle? (k = 1/4πε₀ = 9.0 × 10⁹ N ∙ m²/C²)

A) 1.3 MV
B) 2.9 MV
C) 3.5 MV
D) 7.8 MV