【答案解析】(a)—Responsibilities have to be clearly and carefully defined. —Individual sections lay down a detailed plan of action for a particular area of responsibility. —Section managers have a responsibility to follow their budgets once the budgets have been approved. —The actual performance is periodically monitored and compared with the budgets. —Corrective action is taken if necessary. —Departures from budget are only permitted if they have been approved by senior management. —Variances that are unaccounted for will be subject to further investigation. —Sometimes the budget itself will be changed, so it cannot be done in isolation. (b) Sunny Ltd. Flexible budget for the year ended 31 December 2003 Flexible Budget Variance Actual Costs at 80 % Favourable/(unfavourable) ＄ ＄ ＄ % Direct materials 80,000 75,000 5,000 6.25 Direct labour 240,000 200,000 40,000 16.67 Variable overheads 40,000 43,000 (3,000) (7.5) Total variable costs 360,000 318,000 42,000 11.67 Fixed cost 150,000 170,000 (20,000) (13.33) Total cost 510,000 488,000 22,000