The standards for one case of Seychelles are 14.500 lbs. of raw material were purchased for inventory at a total cost of $81, 200 1, 800 cases of finished product were produced; 13.680 lbs. of raw material were used; 7, 380 labor hours were worked at an average rate of $13.40 per hour. Calculate each of the following variances: Raw materials purchase price variance Raw materials usage variance. Direct labor rate variance. Direct labor efficiency variance Explain the factors that most likely caused the variances computed above