get help with this essay

Identify and discuss the differences between performance-based and contribution-based performance appraisal systems. Identify performance appraisal types and the best-suited appraisals for employee job duties. Identify and explain a variety of performance scales that can be used in the Nike Corp. that include graphical scales, letter scales, and numeric scales. Identify best fit of these scales for performance-based and contribution-based performance appraisal systems. Include at least two references.