Because in the south there was more segregation. Also there was more land that had been untouched in the north. The property was also cheaper because of that reason. And since it was untouched a lot of businesses came in to drill for oil and other natural resources, which created the need for workers.
"<span>b. directly contact the media about creating an ad for the bill" would be the best choice, since this will reach far more people than if you call your representative directly, although you should really do both.</span>