Answer and Explanation:
The computation is shown below:
(a)
Direct material price variance is 
= ($2.5 - $2.55) × 39,600 
= $1,980 Unfavourable 
(b)
 Direct material quantity variance is 
 = (3,400 × 12 - 39,600) × 2.50 
= $3,000 favorable 
(c)
 And, Direct material cost variance is 
= (3,400 × 12 × $2.50) -( 39,600 × $2.55) 
= $1,020 unfavorable 
The same is to be considered