Domestic Quantities Supplied and Demanded?

Question

Qd------price----Qs

700------$6-----1,100

800-------5------1,000

900-------4-------900

1,000----3-------800

1,100----2-------700

1,200----1-------600

1. what would be the price and quantity if the market were closed to international trade?

2. what would be domestic and foreign quantity supplied (for each) if the economy were open to international trade and the world price was $3?

3. Will the graph shift to the right or left? a surplus or a shortage? explain.

please explain the answer so that i know how to do these questions myself next time:)

Answer 1

1) Q=900; P=4; (because Qs=Qd)

2) Qs(domestic)=800; Qs(foreign)=200; it is just difference Qd(at P=3)-Qs(domestic at this price) = 1000-800=200

3) Supply will shift right and domestic suppliers will not be able to supply enough quantities (shortage), and this shortage will be filled by foreign suppliers.