Answer:
 Bianca’s profit per bag is $4,000
Step-by-step explanation:
The computation is shown below:
The actual value paid by the Bianca = Cost of bag × remaining percentage 
 = $4,000 × 40%
 = $1,600
Then it sold 25% higher
So, = Actual value × (100 + profit percentage)
 = $1,600 × (100 + 25%)
 = $2,000
So, the profit would equal to
= $2,000 - $1,600
= $400