Calculate variable cost variances-explain results



Direct materials  ??..5lb@$6.80/lb
Direct Labor????..2.4 hrs@$14.00/hr
Variable overhead??.1.5 hrs @$4.50 hr

During the week ended May 30, the following activity took place 
2,910 machine hours were worked
11,400 lbs of raw material were purchased for inventory at a total cost of $80,940
1,900 cases of finished raw product were produced
4,420 labor hours were worked at an average rate of $14.35 per hour
$12,513 actual variable overhead costs were incurred

Required Calculate each of the following variances and provide
plausible explanations for the results.

A .Price Variance 
B. Raw Materials usage 
C. Direct labor rate variance 
D. Direct Labor efficiency variance 
E. Variable overhead spending variance 
F. Variable overhead efficiency variance