A dipole is placed in uniform magnetic field $\mathrm { B } = 800$ gauss at an angle $30 ^ { \circ }$ then it experiences the torque of $16 \times 10 ^ { - 3 } \mathrm {~N} - \mathrm { m }$. Find the work done in slowly moving the dipole from stable equilibrium to unstable equilibrium.\\
(A) $64 \times 10 ^ { - 3 } \mathrm {~J}$\\
(B) $5 \times 10 ^ { - 3 } \mathrm {~J}$\\
(C) $\mathbf { 2 4 . 5 } \times \mathbf { 1 0 } ^ { - \mathbf { 3 } } \mathbf { ~ J }$\\
(D) $7.6 \times 10 ^ { - 3 } \mathrm {~J}$