Answer and Explanation:
The computation is shown below;
a. The amount of the total dollar sales is
Pretax income  = Sales value - Variable cost - Fixed cost
where, Â
Sales value - variable cost = Contribution margin
$365,100 Â = Contribution margin - $251,000 Â Â Â Â Â
So, Â
Contribution margin = $616,100
Now Â
Contribution margin = Sales value × Contribution margin ratio
$616,100 = Sales value ×  61%
So,
Sales value = $1,010,000
b. The total variable cost is
= Sales - fixed cost - pre tax income
= $1,010,000 - $251,000 - $365,100
= $393,900