What title was held by the monarchs of Iran before the 1979 revolution?

What is the name of the vast grassy plain that is home to Argentina's gauchos? Adults typically have 32 of which body parts that you use to chew? Which Colombian city, about 150 miles northwest of Bogotá, is known as the "City of Eternal Spring"? 32,000 ounces make a short one of these, and about 3,274 more ounces make a metric one. What is it? Which U.S. state has the highest low point, about 3,300 feet above sea level, where the Arkansas River leaves it? Which king took the throne of Macedonia at about age 20 after his father, Philip II, was assassinated in 336 B.C.? About 33.8 fluid ounces equal one of which unit? Which NBA team has retired both Charles Barkley's No. 34 and Wilt Chamberlain's No. 13?