4. (3 Points) Determine the amount of producer surplus [PS] generated in each of the following situations: a. Jack lists his old electric train set on eBay. He sets a minimum acceptable price, known as the reserve price, of $95. After five days of bidding, the final high bid is exactly $95. He accepts the bid. b. Angelina advertises her car for sale in the used-car section of the student newspaper for $2,000, but she is willing to sell the car for any price higher than $1,500. The best offer she gets is $1,800, which she accepts. c. Sanjay likes his social work job so much he would be willing to do it for free. However, his annual salary is $50,000