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Sanford Ltd. produces a product with the following standard cost card Variable overhead (9 hours) $19.40 The fixed overhead rate is based on a standard monthly volume of 15712 The actual results for the month of July 20x5 are as follows: Direct labour (90253 hours) Variable overhead Fixed overhead Units produced and sold $ 1023000 $324429 $580000 What is Sanford's variable overhead spending variance for July 20x5? Note: a negative number represents an unfavourable variance and a positive number represents a favourable variance. Select one O a. -148832 ob. $129884 c. 50 d. S-129884