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Consider the non-downward closed environment of public projects: either every agent can be served or none of them. I.e., the cost structure satisfies: 0 if , = 0, c(3) 0 if , = , and otherwise. (a) Describe the revenue-optimal mechanism for general distribu- tions. (b) Describe the revenue-optimal mechanism when agents' values are i.i.d. from U[0,1]. (c) Give an asymptotic, in terms of the number n of agents, analysis of the expected revenue of the revenue-optimal public project mechanism when agents' values are i.i.d. from U (0,1). Consider the non-downward closed environment of public projects: either every agent can be served or none of them. I.e., the cost structure satisfies: 0 if , = 0, c(3) 0 if , = , and otherwise. (a) Describe the revenue-optimal mechanism for general distribu- tions. (b) Describe the revenue-optimal mechanism when agents' values are i.i.d. from U[0,1]. (c) Give an asymptotic, in terms of the number n of agents, analysis of the expected revenue of the revenue-optimal public project mechanism when agents' values are i.i.d. from U (0,1)