The magentic induction in vacumm at a plaen surface of a magentic is equal to `B` and the vector `B` forms an angle `theta` with the normal `n` of the surface (Fig). The permeability of the magnetic is equal to `mu`. Find:
(a) the flux of the vector `H` through the spherical surface `S` of radius `R`, whose centre lies on the surface of the magentic,
(b) the circulation of the vector `B` around the square path `I'` widh side `l` located as shwon in the fig.