Ответ:
1. They have received the goods. — Haven't they received the goods?
— Yes, they have\No, they haven't.
2. He has finished his work. — Hasn't he finished his work?
— Yes, he has/No, he hasn't.
3. They will visit us on Monday. — Won't they visit us on Monday?
— Yes, they will/No, they won't.
4. We have many customers. — Don't we have many customers?
— Yes, we do/No, we don't.
5. You knew their address. — Didn't you know their address?
— Yes, I did/ No, I didn't.
6. You can do this work. — Can't you do this work?
— Yes, I can/No, I can't.