I would never explain them. I'd get rid of them. My family boycotts all products that advertise in this way.
You'll need to be more specific than this. Are these questions relating to a book or story you have read??
You can look up these terms in either/both of these two websites: http://www.webopedia.com/ http://en.wikipedia.org/wiki/Main_Page
C is incorrect. http://www.answers.com/authoritarian
72/100 = 518.40/x Cross multiply and simplify if needed. Use http://www.wolframalpha.com/ to check your work.
1 and 3 are incorrect. The rest are fine. Remember: who = for subjects (or predicate nominatives after a linking verb) whom = for objects of any kind
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