TEHRAN – Authorities say Iran has executed a once-exiled journalist over his online work that helped inspire nationwide economic protests in 2017.Iranian state television and the state-run IRNA news agency said that Ruhollah Zam was hanged early Saturday morning.In June, a court sentenced Zam to death, saying he had been convicted of “corruption on Earth,” a charge often used in cases involving espionage or attempts to overthrow Iran’s government.Zam’s website and a channel he created on the popular messaging app Telegram had spread the timings of the protests and embarrassing information about officials that directly challenged Iran’s Shiite theocracy.