I have number c) answer but I don't know how they got the that answer out. Can anyone show me step by step how to do it. Thank you!

15. Suppose we are in the market to screwdrivers. In this market supply and demand is given by: Supply: Q = 2p N Demand: Q =60 -P 60 Given these equations above, answer the following questions: a) Under Autarky, what would the market price (p*) and market quantity sold(Q*)? 2 P= 60-P QS - 2 (20 ) Answer here: = 20 3 P = 60 2 = 40 Q* = 40 P = 20 Suppose also that our economy now open up to international trade, and become a small, open economy. The world price for screwdrivers is $30 PW's P * 1 = 20 b) Do we become importer or exporter? If we become importer, what quantity do we produce domestically and what quantity do we import? If we become exporter, what quantity do we export and what quantity do we consume domestically? 60-P= 2P-30 Export: 30 Answer here: 40 +20 = 60 90 = 3P consume domestic : 30 60- 30 = 30 (export) P= 39) How much has Consumer Surplus and Producer Surplus changed as a result of opening to trade compared to being under autarky? Who is made better off and who is made worse off? Note: If you cannot calculate the area, you can draw a figure that shows the area for these changes in CS & PS for half credit Answer here: CS = -350, worse off PS = +500, better off