VIENNA (Reuters) - Iran has produced 17.6 kg of uranium enriched to up to 20% - the point at which it is highly enriched - roughly in line with the 10 kg a month required by a law that made it start that process in January, a U.N. nuclear watchdog report showed on Tuesday. The International Atomic Energy Agency issued an extra report, alongside its regular quarterly one to member states, on Iran’s nuclear activities, both seen by Reuters. The second report said Iran had not yet answered questions on uranium particles found at two sites inspected last year.