Answer:
I sold a used laptop for $108, even though I was willing to go as low as $100 in order to sell it. = Producer Surplus
A local store was having a sale on watches, so I bought a watch for my brother. = Economic Surplus or "Neither"
Even though I was willing to pay up to $37 for a jersey sweater, I bought a jersey sweater for only $30. = Consumer Surplus
Explanation:
"Economic Surplus" refers to the<em> sum of the gain</em> that both consumer and producer have when it comes to selling or buying the product. <u>Both the buyer and seller in the situation above have gains.</u> The buyer was able to have a gain in buying the watch on sale, while the seller considered the profit as a <em>gain rather than as a loss.</em>
"Producer Surplus" refers to the <em>difference between the </em><em>lowest price</em><em> that the seller is willing to sell its product and the </em><em>market price</em><em> of the good.</em> The seller in the situation above is willing to sell as low as $100, but the market price for the laptop is actually higher.
"Consumer Surplus" refers to the <em>difference between the </em><em>highest price </em><em>that a buyer is willing to buy a product and the </em><em>market price</em><em> of the good. </em>The buyer is willing to pay $37 for the jersey sweater, but the jersey sweater costs a lot lower.
So, this explains the answers above.