Now consider clean air, a public (non-rival) good. Each individual has the same demand curve: Pi =10Qi Where: Pi is the willingness to pay by individual i for each unit of clean air. Qi is the quantity of clean air consumed by individual i. 2 Again, compute the aggregate demand for clean air across all 100 identical individuals in the commu- nity. Hint: For non-rival goods like clean air, each person's consumption doesn't detract from another's. So, aggregate demand is the sum of each individual's demand at every price level. ie you want to sum vertically across the population