In spherical coordinates, a current density J = k/(r sin ) a A/m 2 exists in

In spherical coordinates, a current density J = −k/(r sin θ) a_θ A/m² exists in a conducting medium, where k is a constant. Determine the total current in the a_z direction that crosses a circular disk of radius R, centered on the z axis and located at

(a) z = 0;

(b) z = h.