As you learned earlier, project managers are expected by customers and stakeholders to deliver a definitive and functional cost estimate in a timely manner. How do project managers do this? As you discover in your reading, there are three levels of estimation in a project: the WAG, the SWAG, and the "you bet your job on this figure" estimates. Actually, they are referred to in industry as, the "Order of Magnitude" the "Budget," and the "Definitive" cost estimates. The PMBOK addresses them under Analogous, Parametric, and Bottom-up estimates respectively (PMBOK section 6.5.2). Explain which of the three is used where in the project lifecycle.