This document discusses different elements of project costs, including variable costs, overhead costs, and classifications of overhead costs. It also defines key cost accounting terms like marginal cost, marginal revenue, sunk costs, and opportunity costs. Break-even analysis is introduced as a tool to determine the production volume required for a firm to break even. Formulas for total revenue, total costs, contribution, and margin of safety are provided. An example calculation demonstrates how to use these concepts to find the break-even sales quantity, break-even sales, contribution, and margin of safety given fixed costs, variable costs, selling price, and actual production quantity.