$2r$ and current intensity $I,$ flowing in the direction of the arrows. The above right diagram shows two concentric circular currents with radii $r$ and $2r,$ respectively, and the same current intensity $I,$ flowing in the direction of their respective arrows. Points **P** and **Q** are the centers of their respective circular currents. If the magnetic field intensity at point **P** is $B,$ then what is the magnetic field intensity at point **Q**?