JD Group Sales Assistant interview questions

I applied online and got a call the next day asking me to come in for an interview the following week. The manager was very friendly and made me feel at ease. He had about two pages of questions to ask me such as: name a time where you've displayed good customer service. Asked me to name my favourite trainer and how would I sell it to him. How would I then sell Crep Protect as an add-on to the trainer purchase. Describe a time where you've had to deal with an unhappy customer.