Answer:
$4
Step-by-step explanation:
Consumer surplus refers to the difference between the price of a product that a consumer is willing to pay and the amount he actually paid for the product.
Given that,
Actual amount paid coffee = $5
Consumer's willingness to pay for the coffee = $9
Seller's willingness to accept for the coffee = $3
Therefore,
Consumer surplus:
= Consumer's willingness to pay for the coffee - Actual amount paid coffee
= $9 - $5
= $4