Answer The correct answer is 8.317 units
Explanation:
Firstly, calculate the Total fixed costs= ($2.35+$2.63)*6800= $33.864 Fixed Manufacturing and Selling cost
Secondly, calculate the earnings before taxes 63.000/(1-tax rate) = 63.000(/1-0.39)= 103.278.69
Then, Calculate the Revenue less fixed cost  103.278.69+33.864=137.142,68
Then calculate the Variable margin that is equal to ( Price of sales per unit – Variable manufacturing – Variable selling) = (36.10-14.50-5.11)= 16.49
Finally divide the revenue less fixed cost on the variable margin (137.142,68/16.49) = 8316.72
                                      Units                        Price    Total
Revenue                             8,316.72                    36.10      300,233.54  
Fixed Manufacturing                                                  (15,980.00)
Variable manufacturing    8,316.72                    14.50      (120,592.42)
Fixed Selling                                                                    (17,884.00)
Variable Selling                 8,316.72                      5.11         (42,498.43)
Net Revenue                                                                     103,278.69  
Tax rate                                                                39%        (40,278.69)
Total                                                                            63,000.00