Question: The price elasticity of demand for senior citizens purchasing coffee from the coffee shop is -5 while non senior citizens have a price elasticity of demand equal to -1.25. If it cost the coffe shof $0.02 to produce a coffee, the optimal price for a cup of coffee for senior citizens and resultant marginal cost under third-degree price discrimination are, respectively,
A. $0.016 and $0.20
B. $0.02 and $0.80
C. $0.025 and $0.02
D. $0.10 and $0.02