$($a$)$ What is cost behavior analysis? $($b$)$ Why is cost behavior analysis important to man$-$agement?$2.($a$)$ Scott Winter asks your help in understanding theterm "activity index." Explain the meaning andimportance of this term for Scott.$($b$)$ State the two ways that variable costs may bedefined$\mathrm{.}3.$ Contrast the effects of changes in the activity level ontotal fixed costs and on unit fixed costs$\mathrm{.}4.$ J$.$ P$.$ Alexander claims that the relevant range conceptis important only for variable costs.$($a$)$ Explain the relevant range concept. $($b$)$ Do you agree with J$.$ P$.\text{'}$s claim? Explain$\mathrm{.}5.$ "The relevant range is indispensable in cost behavioranalysis." Is this true? Why or why not?