Is it necessary to cite information that is common knowledge or widely accessible, like historical information or popular scientific information, e. g. 70% of the earth is covered in water?

Areal estate salesperson is often approached by home buyers of a particular race. his usual practice is to show them homes in neighborhoods where most of the residents are the same race as the buyers. he avoids showing these buyers properties in integrated areas. this is called:

Reasons for factor mobility of a combine harvester, cotton, an oil platforn and a woodland

What was included in most state constitutions that guaranteed protection of individual liberties based upon common law?