Problem 15-22 (Algo) Calculate variable cost variances-explain results LO 4,5 The standards for one case of liquid weed killer are as follows: Direct materials Direct labor Variable overhead (based on machine hours) 9 lb @ $11.25/1b 5.4 hrs 24/hr 1.8 hr 38.25/hr During the week ended May 6, the following activity took place 6,498 machine hours were worked. 34,542 lb of raw material were purchased for inventory at a total cost of $396,542 3,800 cases of finished product were produced 34,024 lb of raw material were used 20,069 labor hours were worked at an average rate of $24.38 per hour. $51724 actual variable overhead costs were incurred. Required: Calculate each of the following variances (Do not round Intermediate calculations. Indicate the effect of each verlance by selecting "F" Por favorable. "U" for untavorable, and "None" for no effect (1.e., zero varlance)) Price variance for raw materials purchased b. Raw materials usage variance Direct laborate variance d. Direct labor efficiency variance Variable overhead spending variance + Vanable overhead efficiency variance