Answer and Explanation:
The computation of the missing amount is as follows
Components produced   40,000     60,000    90,000
Total cost
Total variable cost       $1,400,000  $2,100,000 $3,150,000
                            (60,000 × $35)   (90,000 × $35)
Total fixed cost          $800,000   $800,000  $800,000
Total cost              $2,200,000  $2,900,000 $3,950,000
Cost per unit
Variable cost per unit     $35        $35      $35
               ($1,400,000 ÷ 40,000) Â
Fixed cost per unit      $20        $13.33     $8.89
($800,000 ÷ 40,000) ($800,000 ÷ 60,000) ($800,000 ÷ 90,000)
Total cost per unit      $55        $46.33     $43.89
The total cost per unit come from
= Variable cost per unit + fixed cost per unit