A long straight wire in the horizontal plane carries a current of $50\;A$ in north to south direction . give the magnitude of B at a point $2.5\;m$ east of the wire

Question

$\begin{array}{1 1} 4 \times 10^{-6}\;T \\ 5 \times 10^{-3}\;T \\ 3.5 \times 10^{5}\;T \\ 3.5 \times 10^{4}\;T\end{array}$