you are the manager of a firm that reveive revenue of Rs.30,000 per year from product X and Rs. 70,000 per year from product Y. The own price elasticity of demand for product X is -2.5 and the cross price elasticity of demand between product Y and X is 1.1 . how much will you firm's total revenue ( revenue from both products) change if you increase the price of good X by 1 present?