BEIJING (AP) — China’s factory activity was flat in May, according to an official survey released Sunday, raising questions about how much further the country’s economy can shield itself from the fallout of the ongoing Iran war and pressure on demand. The official manufacturing purchasing managers index moderated to 50 from 50.3 in April , according to the National Bureau of Statistics. Measured on a scale between 0 and 100, a PMI reading above 50 indicates expansion, while a reading below 50