Use the data in the table in Problem 16.

a. If the sandwich market is efficient, what is the consumer surplus, what is the producer surplus, and what is the total surplus?

b. If the demand for sandwiches increases and sandwich makers produce the efficient quan- tity, what happens to producer surplus and deadweight loss? Use the following news clip to work Problems 19,20, and 21. Spotify Won't Raise Its Music Streaming Prices-Yet As streaming services solidify their position as the dominant way that people listen to music, a com- mon question swirling around has been whether subscription prices will go up. Over the past decade, Spotify has helped set a US. market standard of $9.99 per month for a premium music subscription; it hasn't adjusted that figure once. Source: rollingstone.com, September 18, 2019 Assume that the marginal social cost of streaming is zero. (This assumption means that the cost of operat- ing a streaming service doesn't change if more people stream more songs.)