Anthony & Bruce Co. produces and sells one type of metal rack. For the month ended 31 October 2021 the following information has been established:

Production 1,100 racks

Sales 840 racks

Revenue $ 46,000

Material used 33,600 kg at a total cost of $ 20,832

Labour hours worked 1,820 at a total cost of $ 7,462

Variable production overhead incurred $ 10,500

Fixed production overhead incurred $ 15,500

The following standard and budgeted information is also available:

Standard material cost per mould 30 kg at a standard price of $ 0.60 per kg

Standard labour hours per mould 1.75 hours at a standard rate of $ 4.00 per hour

Variable production overhead $ 6.00 per labour hour

Fixed production overhead $ 9.00 per labour hour

Budgeted fixed production overhead $ 189,000 per year

Budgeted production and sales 1,000 racks per month

Budgeted unit selling price $ 54

Based on the information provided above, calculate the following variances for the month ended 31 October 2021:

1. Labour efficiency
2. Variable production overhead expenditure
3. Variable production overhead efficiency