Answer:
1) using conventional costing 
unit cost mercon = $98
unit cost wurcon = $297
2) using ABC costing
unit cost mercon = $218
unit cost wurcon = $237
Explanation:
                                                      Mercon           Wurcon
Direct materials cost per unit       $8.00             $6.00
Direct labor cost per unit            $10.00             $11.00
Direct labor-hours per unit            2.00                7.00
overhead rate applied                     $80              $280      
Number of units produced           1,000              2,000
overhead rate = total overhead / total direct labor hours = $640,000 / 16,000 = $40
unit cost mercon = $8 + $10 + $80 = $98
unit cost wurcon = $6 + $11 + $280 = $297
using the ABC costing, overhead rate is only 50%
Mercon           Wurcon
Direct materials cost per unit       $8.00             $6.00
Direct labor cost per unit            $10.00             $11.00
Direct labor-hours per unit            2.00                7.00
overhead rate applies                     $40              $140      
Number of units produced           1,000              2,000
total engineering costs          $160,000        $160,000
engineering cost per unit              $160                $80
engineering cost per unit = $320,000 / 2,000 = $160
unit cost mercon = $8 + $10 + $40 + $160 = $218
unit cost wurcon = $6 + $11 + $140 + $80 = $237