Answer and Explanation:
1. The total amount of traceable fixed manufacturing overhead is given below:-
                                                  Alpha            Beta
Number of units produced   100,000       100,000
Traceable fixed 
manufacturing overhead      $16                 $18
Total amount of traceable fixed 
manufacturing overhead $1,600,000  $1,800,000
2.  The total amount of common fixed expenses is given below:-
                                                  Alpha            Beta
Number of units produced   100,000       100,000
Common fixed 
manufacturing overhead       $15                 $10
Total amount of common fixed
manufacturing overhead     $1,500,000  $1,000,000
3. The computation of increase or decrease of profit is shown below:-
Selling price                        $80
Less: Variable cost
Direct material                   ($30)
Direct labor                        ($20)
Variable manufacturing 
overhead                             ($7)
Contribution margin           $23
Less: Variable selling 
expenses                            ($12)
Profit per unit                       $11
Total profit increase 
(10,000 × $11)                      $110,000
The computation of increase or decrease of profit is as shown below:-
Selling price                        $39
Less: Variable cost
Direct material                   ($12)
Direct labor                        ($15)
Variable manufacturing 
overhead                             ($5)
Contribution margin           $7
Less: Variable selling 
expenses                            ($8)
Profit per unit                       ($1)
Total profit decrease
(5,000 × -$1)                      -($5,000)