Answer:
Accept the offer because it will generate incremental net income of $12,600
Explanation:
If Oak accepts the offer, its incremental revenue would be;
4,200 × $70 = $294,000
Its incremental cost would be ;
4,200 × $67 = $281,400
Incremental net net income for the order would be ;
$294,000 - $281,400 = $12,600. Accept the offer.