Describe various top-down and bottom-up estimating methods, and compare and contrast these methods in terms of their advantages and disadvantages and contexts to which each is best suited. 2-2) Discuss the advantages and disadvantages of various estimating guidelines for time, cost, and resources. 2-3) Discuss best practices for estimating time and costs, and the importance of building slack time into estimates. 2-4) Describe and contrast Risk Assessment and Contingency Planning methods