5. Assume that we have estimated a demand curve for a particular brand of car. Using a diagram, show the potential impacts of the following: (a) a rise in the price of petrol; (c) a fall in the price of the car; (b) a rise in the price of the car; (d) a general rise in incomes; (e) the invention of a water-powered car; (f) the introduction of a new model by a competing car manufacturer. (g) an advertising campaign by a competing car manufacturer