Question 3 (25%): Economics of Health Externalities. Scientists have discovered new vac- cines for diseases A and B. The private and social demand curves for each vaccine are: private = 50 - P (1) social = 100 - P (2) private = 50 - 2P (3) social = 120.711 - 2P (4) 1. (5%) Which vaccine faces a more elastic demand? 2. (5%) Is there an externality for vaccines A and B? 3. (15%) Calculate the social loss for both vaccines (round to integer). Interpret the result. [ Hint: Draw the graphs and calculate the triangle area.]