Assume the following: The variable portion of the predetermined overhead rate is $1.50 per direct labor-hour. The standard labor-hours allowed per unit of finished goods is 3 hours. The actual quantity of labor hours worked during the period was 43,350 hours. The total actual variable manufacturing overhead cost for the period was $63,000. The company produced 15,000 units of finished goods during the period. What is the variable overhead rate variance?