Answer and Explanation:
A. The preparation of the differential analysis dated January 21 on whether to reject (Alternative 1) or accept (Alternative 2) the special order from Euro Motors is presented below:
                                             Differential analysis
                         Reject (Alternative 1) or accept (Alternative 2)
                                                              Jan 21
Particulars     Reject order        Accept order    Differential effect on income
                     (Alternative 1)     (Alternative 2)     (Alternative 2)
Revenues 
(26,000 tires × $93.6)             $2,433,600          $2,433,600
Less: cost
direct material 
(26,000 tires × $54)               -$1,404,000            -$1,404,000
Direct labor 
(26,000 tires × $24)               -$624,000               -$624,000
Variable factory overhead 
(26,000 tires × $24 × 0.62)   -$386,880               -$386,880
Variable selling and admin expenses
(26,000 tires × $25 × 0.44) - ($114 × 4%)
                                               -$167,440                -$167,440
Shipping cost 
(26,000 tires × $7.65)           -$198,900                 -$198,900
Certification cost                  -$165,424                  -$165,424
Income or loss                       -$513,044                   -$513,044
B. As we can see that there is a loss of   -$513,044 so the special order should be rejected
C. The minimum price is 
= Selling price - differential income per unit
= $93.6 - (-$513,044 ÷ 26,000 tires)
= $93.6 - (-$19.73)
= $113.33