A retailer spends $500 per month to keep its online shop active and updated. The store acquires shirts at a marginal cost of $5 per shirt. Each shirt sells
for a marginal benefit of $10 per shirt.
What is the minimum number of shirts the retailer needs to sell in order to
pay for all its costs in a month?
Quantity of shirts sold Marginal cost Total cost Marginal benefit
0
$0
$500 $0
25
$125
$625 $250
50
$250
$750 $500
75
$375
$875
$750
100
$500
$1,000
$1,000
125
$625
$1,125
$1,250
O A. 100
O B. 25
O c. 125
O D. 75