The figure shows the section of a long coaxial cable. The radii of its metal veins are R1 = 2 mm, R2 = 3 mm, r = 2 mm, and the currents in them are I1 = 6 A, I2 = 2 A. Given that the currents I1 and I2 flow in different directions, The dependence of the magnetic field induction, stored between the metal conductors of the cable per unit of its length.

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