12. Table 7.5 contains information about an environmental cleanup project in the township of Hiles. Shorten the project three weeks by finding the minimum-cost schedule. Assume that project indirect costs and penalty costs are negligible. Identifyactivities to crash while minimizing the additional crash costs.a. What is the project’s duration if only normal times are used?b. What is the minimum-cost schedule?c. What is the critical path for the minimum-cost schedule?