Warner Manufacturing has established the following master flexible budget for the current year:

Production in Units

80,000

120,000

160,000

Variable expenses:

Raw materials

$152,000

228,000

304,000

Direct labour

160,000

240,000

320,000

Manufacturing overhead

120,000

180,000

240,000

Total variable expenses

$432,000

$648,000

$864,000

Fixed expenses:

Manufacturing overhead

$300,000

$300,000

$300,000

Selling and administrative

192,000

192,000

192,000

Total fixed expenses

$492,000

$492,000

$492,000

Total expenses

$924,000

$1,140,000

$1,356,000

Manufacturing overhead is applied on the basis of machine hours. At standard, each unit of product requires one machine hour to complete.

Required:

a) The denominator activity level is 120,000 units. What are the predetermined variable and fixed manufacturing overhead rates?

b) Actual data for the year were as follows:

Actual variable manufacturing overhead cost

$159,500

Actual fixed manufacturing overhead cost

$305,000

Actual machine hours incurred

110,000

Units produced

105,000

(i) Compute the variable overhead spending variance for the year

(ii) Compute the variable overhead efficiency variance for the year

(iii) Compute the fixed overhead budget variance fopr the year

( iv) Compute the fixed overhead volome variance for the year