# $\mu_0$ and $\in_0$ denote the permeability and permittivity of free space, dimension of $\mu_0 \in_0$ are
$\begin{array}{1 1} (a) \;LT^{-1}\\ (b) \;LT^{-2}T^{2} \\ (c) \;M^{-1}L^{-3}Q^2T^{2} \\ (d) \;M^{-1}L^{-3}Q^2T^{-2} \end{array}$