Most countries have a mixed economy true or false? Sorry this is a dumb question but idk

Define production possibility curve

Read the quote about government in iran. “we thought that mr. khatami’s victory was a victory for us as well. the election of a more democratic government seemed to be a bright new beginning . . but within less than a year of the election, the journalists, reformists, and intellectuals began to be persecuted by hard-liners in the judiciary and intelligence ministry . .” —camella entekhabifard, “tehran’s eternal youth,” new york times based on this quote, how does camella entekhabifard feel about the iranian government? a. she supports reforms and was disappointed when they did not come about. b. she supports hard-liners who want the supreme leader to have more power. c. she believes reformers should be silenced to keep iran's government strong. d. she supports a more democratic government but opposes freedom of speech.

If both the president and the vice president can no longer serve, who will become the next head of state?