“[In the Middle Ages] there are a lot of different societies ... an associate professor from Colorado State University is discovering through high-tech archaeological studies in Central Asia ...
Far from their dour reputation, the Middle Ages were a period of massive social change, burgeoning nationalism, international conflict, terrible natural disaster, climate change, rebellion ...
For example, the note middle C on a keyboard ... 3,000 children between the ages of 9 and 11. They found that 14 percent of the children had some degree of high frequency hearing loss.