please answer

Question 3 A market has the following structure Demand: Q=20-P Supply: Q=0.25P Production of the good creates $5 in externality. Find the quantity with a $10 Pollution Tax. Question 4 A market has the following structure Demand: Q=20-P Supply: Q=0.25P Production of the good creates $5 in externality. Is society better off, worse off, or the same with this non-optimal $10 per unit tax than the market outcome with no tax? O Worse off O Same O Better off