Figure E28.40 shows, in cross section, several conductors that carry currents throug...

Figure E28.40 shows, in cross section, several conductors that carry currents through the plane of the figure. The currents have the magnitudes I₁ = 4.0 A, I₂ = 6.0 A, and I₃ = 2.0 A, and the directions shown. Four paths, labeled a through d, are shown. What is the line integral for each path? Each integral involves going around the path in the counterclockwise direction. Explain your answers.