Answer:
Answer is explained in the explanation section below. 
Explanation:
Solution: 
a. 
In part a, we need to find the following 3 requirements: 
1. Direct Materials Price Variance
2. Direct Materials Quantity Variance
3. Total Direct Materials Cost Variance
Direct Materials Price Variance: 
It can be calculated by using the following formula: 
DMPV = AQ multiplied by (AP minus the SP)
Where,  
DMPV = Direct Materials Price Variance
AQ = Actual Quantity 
AP = Actual Price 
SP = Standard Price 
We do have all the data, so just plug in the values into the above equation to get the DMPV. 
AQ = 101,000 
AP  = 6.50 USD 
SP = 6.40 USD 
So, 
DMPV = 101,000 ( 6.50 - 6.40)
DMPV = 10,100 USD 
Direct Materials Quantity Variance: 
DMQV = SP ( AQ - SQ ) 
Where, 
DMQV = Direct Materials Quantity Variance = ?
SP  = Standard Price  = 6.40 USD
AQ = Actual Quantity  = 101,000
SQ = Standard Quantity  = 100,000
Plugging in the values: 
DMQV  = 6.40  ( 101,000 - 100,000)
DMQV = 6400 USD 
Total Direct Materials Cost Variance: 
DMCV = SMC - AMC 
Where, 
DMCV =  Direct Materials Cost Variance = ?
SMC = Standard Market Cost = 6.40 USD x 100,000
AMC = Actual market Cost = 6.50 USD x 101,000
DMCV = (6.40 USD x 100,000) - (6.50 USD x 101,000)
DMCV = 640,000 - 656,500
DMCV =  16,500 USD 
b. 
For part b, we need following particulars: 
1. Direct Labor Rate Variance (DLRV)
2. Direct Labor Time Variance (DLTV)
3. Direct Labor Cost Variance  (DLCV) 
Direct Labor Rate Variance (DLRV) :
DLRV = (ADLR - SDLR) x ADLH
Where, 
ADLR  = Actual Direct Labor Rate = 15.40 USD 
SDLR = Standard Direct Labor Rate = 15.75 USD 
ADLH = Actual Direct Labor Hour = 2000
So, 
DLRV = (ADLR - SDLR) x ADLH 
DLRV =  (15.40 USD  - 15.75 USD  ) x 2000 
DLRV = 700 USD 
Direct Labor Time Variance (DLTV): 
DLTV = ( ADLH - SDLH ) x SDLR 
SDLH = Standard Direct Labor Hour = 2080
DLTV = ( 2000  - 2080 ) x 15.75 USD  
DLTV = 1260 USD 
Direct Labor Cost Variance  (DLCV) 
DLCV = SDLC - ADLC 
SDLC = Standard Direct Labor Cost  
ADLC = Actual Direct Labor Cost
DLCV =  (1540 x 2000) - (15.75 x 2080) 
DLCV = 1960 USD 
c. 
For Part c, we need following: 
1. variable factory overhead controllable variance (VFOCV)
2. fixed factory overhead volume variance (FFOVV) 
3. Total factory overhead cost variance (TFOCV)
 variable factory overhead controllable variance (VFOCV): 
VFOCV =  AFO - B 
Where, 
AFO = Actual Factory Overhead  = 8200
B = Budgeted Allowance Based on Standard Hours Allowed = 4160x0.5x4
B = 8320 USD 
VFOCV =  8200 - 8320  
VFOCV =   120 USD 
fixed factory overhead volume variance (FFOVV) : 
FFOVV = (S - BH ) x SOR
Where, 
S = Standard Hours for actual output = 4160 x 0.5 
BH = Budgeted Hours = 2080
SOR = Standard Overhead Rate = 6 USD 
FFOVV = (4160 x 0.5  - 2080) x 6 
FFOVV =  0 USD 
Total factory overhead cost variance (TFOCV): 
TFOCV = AFO - SO 
Where, 
AFO = Actual Factory Overhead = 20,200
SO = Standard Overhead = 2080 x 10 
TFOCV =  20,200 - ( 2080 x 10  ) 
TFOCV =  600 USD