Answer:
See below
Step-by-step explanation:
Sales ($30 × 1,000 drives sold)
$30,000
Less:
Variable cost ($6 × 1,000 drives sold)
($6,000)
Contribution margin
$24,000
Less:
Fixed costs
($6,000)
Operating profit
$18,000
Therefore, Bonita's operating income increases by $18,000 per month