Which middle eastern country that lies between Iraq and Afghanistan used to be called Persia and why is the Persian Gulf important to this country's economy?

Answer 1

There are two questions here:

Question 1) Which middle eastern country that lies between Iraq and Afghanistan used to be called Persia? -- The Middle Eastern country between Iraq and Afghanistan is Iran.

Question 2) Why is the Persian Gulf important to this country's economy? -- The Persian Gulf is very important to Iran for a number of reasons. The primary reason is that it provides a mechanism for Iran to export its petroleum around the world. It also provides Iran access to an incredible amount of seafood, trade, and cultural interaction with its neighbors.