I have few questions regarding quotations.

1- Quotations in essay..

i- How many quotations should be write in the essay?
ii- Right place of quotation in the essay, in the start, mid or in the end?
iii- Quotation points se relate kar kay likhni chahye ya randomly bhi llikh saktay hain,?
iv- Can we use quotations as a definition? I mean pahle quotations then introduction?
v- what is the right way to write quotation’s i.e. "Poverty is the parent of revolution and crime." Aristotle OR Aristotle very rightly said that “poverty is the parent of revolution and crime”….?

2- Quotations in questions of 20 marks.

i- How many quotations should be write in the simple question of 20 marks?
ii- Right place of quotation in the question, in the start, mid or in the end?
iii- Can we use quotations as a definition?
iv- what is the right way to write quotation’s i.e. "Poverty is the parent of revolution and crime." Aristotle OR Aristotle very rightly said that “poverty is the parent of revolution and crime”….?

Please elaborate me all above mentioned questions.
Regards.