Fluorspar Company's standard variable overhead rate is $4.00 per direct labor hour, and each unit requires 3 standard direct labor hours. During March, Fluorspar recorded 3,000 actual direct labor hours, $40,000 actual variable overhead costs, and 2,500 units of product manufactured. What is the total variable overhead variance for March for Fluorspar? a. $8,000 U b. $14,000 U c. $10,000 U Od. $6,000 u