The demand curve for a product is given by: Q = 900 − 40P, where Q is the quantity demanded and P is the price of the product. If the initial price of the product is ₹15, what is the price elasticity of demand (point elasticity) if the price increases to ₹20?

Compute the price elasticity of demand for the given data: Initial Quantity (Q1) = 10, Initial Price (P1) = 10 New Quantity (Q2) = 20, New Price (P2) = 5

Consider the demand function for Good A: QA = 100 − 2PA + 0.2Y + 0.3PB with PA = 6, Y = 500, PB = 10 (so QA = 191). Calculate the cross-price elasticity of demand for Good A with respect to PB and determine the nature of the relationship between Good A and Good B: