1. Irfaan loves black coffee. A roadside stall selling a cup of black coffee at Rs. 120, offered 25% discount to Irfaan. If Irfaan was willing to pay even Rs. 200 for this cup of black coffee, Irfaan's consumer surplus is
5. If hiring an extra worker increases a factory's output from 1000 to 1200 units per day, but the factory has to reduce the price of its product from Rs. 25 to Rs. 24 per unit to sell the additional output, the marginal revenue product of the last worker is
8. If price of an article decreases from Rs. 25 to Rs. 20, quantity demanded increases from Q1 units to 1500 units. If point elasticity of demand is -1.25, find Q1?