8. John has been in the habit of mowing Willa's lawn each week for $20. John's opportunity cost is $15, and Willa would be willing to pay $25 to have her lawn mowed. What is the maximum tax the government can impose on lawn mowing without discouraging John and Willa from continuing their mutually beneficial arrangement

Power plants that rely on coal increase the amount of sulfur dioxide that dissolves into the air, eventually increasing the acidity of precipitation. the higher acidity of rain and snow can damage forests by making it more difficult for plants to absorb minerals from the soil. the equations below provide information about the market demand and supply of electricity. there is a constant marginal external cost of $25 per unit of electricity.d: qd= 200 – 2ps: qs=p – 10what quantity of electricity satisfies allocative efficiency in this market? a. 60b. 70c. 50d. 43.3