The document provides notes on process costing systems, costing of joint and by-products, marginal and absorption costing, cost-volume-profit analysis using both the contribution margin and break-even approaches, and margin of safety. It discusses two methods for process costing, bases for allocating joint costs, the treatment of fixed costs under marginal and absorption costing, assumptions and formulas for cost-volume-profit analysis, and defines margin of safety and the margin of safety ratio.