The magnetic bearing of the sun for a location at noon is $ 183^{\circ} \; 30^{\prime}$. If the sun is exactly on the geographic meridian at noon, the magnetic declination of the location is ____________.
- $3^{\circ} \; 30^{\prime} ~ \mathrm{W}$
- $3^{\circ} \; 30^{\prime} ~ \mathrm{E}$
- $93^{\circ} \; 30^{\prime} ~ \mathrm{W}$
- $93^{\circ} \; 30^{\prime} ~ \mathrm{E}$