Answer for (a): benefits of the market. Consumer surplus occurs when consumers invest less than their capacity to pay for products or services. The value added is calculated under the basis that consumers spend less on something than they have been able to afford[1] .
WWhereas, the surplus of the producer is an economic calculation that measures the difference between the volume of the commodity actually generated by the company and the minimum amount allowed by the company. This difference is the excess between the amount paid by the customer and the minimum fixed price[2] . For example, if a producer is willing to sell a good for TK4, but is able to sell it for TK10, the producer surplus would be TK6.