18. Show in a diagram the effect on the demand curve, the supply curve, the equilibrium price, and the equilibrium quantity of each of the following events. a) There is a hike in the wages of agricultural labourers. And at the same time, due to a change in the tax code, the incomes of farm operations that hire ag labor declines. b) The price of coffee increases. At the same time, robots for mechanical pruning and harvesting are developed which lower the cost of production of tea. 19. The Demand and Supply curves for small square bales of alfalfa hay in Corvallis are given by - D = 110 - 4P and S = 10+P where, P is the price of a bale of alfalfa hay- a) In this market, what is the quantity of bales of hay bought and sold at equilibrium? What is the equilibrium Price? Show in a diagram. b) Assume that price of hay bales increases by $1. What is the new equilibrium price and quantity? What