They where big trading cities that many people wanted to control and because of it geographic location it was used as a cultural hearth
June 21st is the solstice for summer so the season is winter in the southern hemisphere.
Self-report data asks respondents to reveal illegal activity in which they have been involved, to which they are able to plead the 5th in order to not incriminate themselves, the risk in which being they place automatic suspicion upon themselves