Answer:
The question is incomplete, it is missing the accounts and numbers, so I looked for a similar question: 
<em>The Rehe Comany sells its razors at $3 per unit. The company uses a first-in, first-out actual costing system. A fixed manufacturing cost rate is computed at the end of each year by dividing the actual fixed manufacturing costs by the actual production units. The following data are related to its first two years of operation:
</em>
<em>                    2011 2012
</em>
<em>Sales 1000 units  1200 units
</em>
<em>Costs:
</em>
<em>Variable manufacturing  700 500</em>
<em>Fixed manufacturing  700 700</em>
<em>Variable operating (marketing) 1000 1200
</em>
<em>Fixed operating (marketing)  400 400</em>
<em />
                                                            2011                  2012
Sales                                               1000 units         1200 units
Production                                          1400                  1000  
Costs:  
Variable manufacturing                      $700               $500
per unit $0.50
Fixed manufacturing                           $700               $700
Variable operating (marketing)         $1000             $1200
Fixed operating (marketing)               $400               $400
cogs under absorption costing 2011 = ($1,400 / 1,400) x 1,000 = $1,000
cogs under absorption costing 2012 = $400 + ($1,200 / 1,000) x 800 = $1,360
1.                                    INCOME STATEMENTS
                                       VARIABLE COSTING
                                                              2011                    2012
Total sales revenue:                        $3,000                $3,600            
Opening inventory:                               ($0)                 ($200)
Variable manufacturing:                   ($700)                 ($500)
<u>Ending inventory:                               $200                   $100
</u>
Gross contribution margin:             $2,500               $3,000
<u>Variable operating:                         ($1,000)              ($1,200)</u>  <u>
</u>
Contribution margin:                        $1,500                $1,800  
Fixed manufacturing:                         ($700)                ($700)
<u>Fixed operating:                                ($400)                ($400)
</u>
Net operating income:                       $400                  $700
2.                                   INCOME STATEMENTS
                                    ABSORPTION COSTING
                                                              2011                    2012
Total sales revenue:                        $3,000                $3,600            
<u>COGS:                                             ($1,000)                ($1,360)
</u>
Gross margin:                                  $2,000                $2,240
<u>Operating costs:                             ($1,400)               ($1,600)
</u>
Net operating income:                       $600                   $640
3. Under variable costing, closing inventory = 400 units x $0.50 (variable production costs per unit) = $200.
Under absorption costing, closing inventory = 400 units x $1 (production cost per unit) = $400
Since closing inventory is $200 higher under absorption costing, then net operating income during 2011 increases by $200.
4. a) Variable costing is more likely to result in inventory buildups. Since variable costing determines the value of closing inventory only using variable manufacturing costs, their value is much lower. E.g. in this case the value of closing inventory 2011 under variable costing is $200, while under absorption costing it is $400. This means that less costs are transferred from one year to another.
b) Cost of goods sold must include all production costs (both variable and fixed). This way COGS costs cannot be over estimated during one year and under estimated the next.
<em>
</em>
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