Suppose that it costs $400 per day to search for chanterelle mushrooms at Pt. Reyes National Seashore. On an average day, the total weight of mushrooms M found at Pt. Reyes is M=100x-x^2 pounds ,where X is the number of people mushroom hunting on that day. Chanterelles can be sold for $90 per pound. How many more people will go mushroom hunting than is socially optimal?

What outputs a and b (in millions of dollars per year) should the two industries generate to satisfy the demand? you may be tempted to say 1,000 and 780, respectively, but things are not quite as simple as that. we have to take into account the interindustry demand as well. let us say that industry a produces electricity. of course, producing almost any product will require electric power. suppose that industry b needs 1o¢ worth of electricity for each $1 of output b produces and that industry a needs 20¢ worth of b's products for each $1 of output a produces?