Emily sets up a lemonade stand. She has set-up costs of and each cup of lemonade costs her to make. She sells each cup of lemonade for .
(a) What is the total cost, including the set-up, for her to make 100 cups of lemonade?
(b) What is her profit (money earned minus total cost) if she sells 100 cups of lemonade?
(c) What is the number of cups that she must sell to break even (that is, to have a profit of )?
(d) Why is it not possible for her to make a profit of exactly ?
, 2009
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