Probably some details are missing like the length of CD or AB or BC... Area is given, we needed to know the angles.
In a parallelogram the adjacent angles are supplementary ie., sum is 180 deg.
angle C + angle D = 180.
If angle C > angle D, then OC < OD, So the fire station at C is nearer to the fire at O. So choose the firestation at the obtuse angle rather than at the acute angle.
If angle D = angle C, then OC = OD. Then both stations are equi-distant.