This report discusses the calculation of variances in management accounting and the make-or-buy decision for a company. It includes information on sales price variances, sales volume contribution variances, material price planning variance, material price operational variance, and the analysis of variances. The report also analyzes the merits and demerits of using variances to determine managers' performance. Additionally, it discusses the make-or-buy decision for a specific product and provides a cost analysis for in-house production.