it will be great if some account experts can answer my 10 of this questions.

QUESTIONS 3-1 What is a cost driver? Give three examples of costs and their possible cost drivers. 3-2 Explain linear-cost behavior 3-3 Step costs can be fixed or variable, depending on your perspective." Explain. 3-4 Explain how mixed costs are related to both fixed and variable costs. 3-5 How do management's product and service choices affect cost behavior? 3-6 Why are fixed costs also called capacity costs? 3-7 How do committed fixed costs differ from discretionary fixed costs? 3-8 Why are committed fixed costs the most difficult of the fixed costs to change? 3-9 What are the primary determinants of the level of committed costs? Discretionary costs? 3-10 "Planning is far more important than day- to-day control of discretionary costs." Do you agree? Explain