The current density in a wire of radius R varies with radial distance r as $j=\lambda r^2,$ where $\lambda$ is a constant
I. Total current passing through the cross-section of wire is $\frac{\pi \lambda R^4}{2}$  
II. The field at distance r > R is $\frac{{\mu }_0\lambda R^4}{4r}$ 
III. The field at distance r < R is $\frac{{\mu }_0\lambda r^3}{4}$