In a random sample of 545 accountants engaged inpreparing county operating budgets for use in plan-ning and control, 117 indicated that estimates of cashflow were the most difficult element of the budget toderive.a. Test at the 5% level the null hypothesis that at least25% of all accountants find cash flow estimates themost difficult estimates to derive.b. Based on the procedure used in part a, what isthe probability that the null hypothesis wouldbe rejected if the true percentage of those findingcash flow estimates most difficult was each of thefollowing? i. 20%ii. 25%iii. 30%