Name the black people Isabel has interacted with before the debate, and the relationship the black people had with the Dyson family.

From the text:

I’m not saying I’ve had no contact across the color line. Good heavens no! I get as much of that as any average young white South African. I have a great time every morning with Auntie in the kitchen when she’s cooking breakfast and we gossip about everything and everybody in town. And then there’s Samuel with his crash helmet and scooter ... he delivers medicines for my dad ... I have wonderful long conversations with him about religion and the meaning of life generally. He’s a very staunch Zionist. Church every Sunday. But it’s always “Miss Isabel,” the baas's daughter, that he’s talking to.