English Conversation Practice - After Sales Service

Customer: If I need help with the computer after I take it home who should I call?
Sales clerk: Please call us. We offer after sales service.
Customer: What is that?
Sales clerk: We are here to help and support you with your new product after you leave the store.
Customer: Is there an extra charge for this service?
Sales clerk: No, not at all. If you need help with installation or operation, please call our store any time.

1. What does the customer buy?
Car
Computer
Boat
Television

2. What does the store offer to the customer?
Refund
Exchange for another product
After sales service
Installation charge

3. What kind of help does the store give to the customers?
Installation
Operation
Both A and B
None of the above