You sell a given product through 1000 shops, and the average revenue for that product is K2.4 per month per shop, with a standard deviation of K3.

You sell a given product through 1000 shops, and the average revenue for that product is K€2.4 per month per shop, with a standard deviation of K€3.1. You want to analyze if the offer "take 3, pay 2" would be effective on your revenue. To do that, you introduce the offer in 50 shops for 1 month. Describe which data you would collect and what you would do with them. Would you recommend any special care in selecting the shops?