On 25 February 2020, Nancy Messonnier, an official of the US Centers for Disease Control and Prevention, warned that the coronavirus outbreak could cause "severe disruption." At that time, the virus had afflicted over 81,000 persons and caused 2,762 deaths worldwide. Meanwhile, the price of 100 basic sanitary masks had more than trebled from US$4.21 to US$14.99.

1. Discuss the price elasticity of the short-run supply of face masks in the United States.
2. Using suitable demand and supply curves, explain the effect of the Covid-19 outbreak on the short-run equilibrium in the market for face masks.
3. Discuss the price elasticity of the long-run supply of face masks in the United States.
4. On your figure in (b), draw the long-run supply curve and discuss the differences between the short- and long-run equilibria.