B. Flase 9] The variance that is usually most useful in assessing the performance of the purchasing department manager is: A. the materials quantity variance B. the materials price variance C. the labor rate variance. D. the labor efficiency variance [2] Which of the following factors would cause an unfavorable material usage variance? A. using poorly maintained machinery B. using higher quality materials C. using more highly skilled workers D. receiving discounts for purchasing larger than normal quantities