The consumer surplus for Charlie would be $1 if he buys the t-shirt,
The term consumer surplus is associated with the difference between the prices that a consumer is willing to pay to buy a particular product and its market price. It is also abbreviated as CS.
Consumer surplus(CS) is computed as:
CS = Consumer's willingness to pay - Market Price
CS = $10 - $9
CS = $1
Therefore, the consumer surplus for Charlie would be $1.
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