please show all calculations and explanation please

Amazoncom, the online bookseller, wants to increase its total revenue. One strategy is to offer a 10% discount on every book it sells. Amazoncom knows that its customers can be divided into two distinct groups according to their likely responses to the discount. The accompanying table shows how the two groups respond to the discount. Group A. [sales pet week} Group B [sales per week] Volume of sales before 1.55 million 1.50 million the 10% discount Volume of sales after 1.65 million 1.70 million the 10% discount 1- Using the midpoint method, calculate the price elasticities of demand for group A and group B. {10 marks) 2. Explain how the discount will affect total revenue from each group. (5 marks) 3. Suppose Amazoncom knows which group each customer belongs to when he logs on and can choose whether or not to offer the 10% discount. If Amazoncom wants to increase its total revenue, should discounts be offered to group A or to group B, to neither group, or to both groups? {5 marks}