The following information pertains to Davma Corporation for the month of March: Actual overhead costs were $160,000. Of that amount, $43,000 was fixed. Direct labour: Actual hours worked 18,000 hours Standard hours allowed for actual production 15,000 hours Average actual labour cost per hour $30 At Davma Corporation, the overhead rate is based on a normal volume of 18,000 hours. At 18,000 direct labour hours, standard cost data were as follows: Variable overhead Fixed overhead Total overhead $108,000 36,000 $72,000 Required (A) What is the corporation's variable overhead efficiency variance? Is it favourable or unfavourable? (B) What is the corporation's variable overhead spending variance? Is it favourable or unfavourable? (C)What is the corporation's fixed overhead spending variance? Is it favourable or unfavourable? (D) How do the variable overhead variances and the fixed overhead variances help managers (i.e., what do the variances tell us)