The standard cost of product 2525 includes 2.65 hours of direct labour at $14.55 per hour. The predetermined overhead rate is $22.30 per direct labour hour. During July, the company incurred 4,440 hours of direct labour at an average rate of $14.85 per hour and $92,452 of manufacturing overhead costs. It produced 1,600 units.

a. Calculate the total, price, and quantity variances for labour.

b. Calculate the total overhead variance.