Its an Economics Question Assume that the market of air-tickets is a perfectly competitive one. Using graphical illustration, evaluate the effect on the equilibrium price and quantity of air-tickets if the following events occur. a) The price of the aircraft fuel increases. (5 marks) b) Consumers' incomes decrease because of recession. (5 marks) c) The price of a train tickets (a form of substitute) falls. (5 marks) d) The price of hotel accommodation (complementary items in a travel package) increases. (5 marks)