10. On each question in this contest you receive five marks for each correct answer, one mark for no an-
swer, and zero marks for an incorrect answer. Suppose that for six questions on the contest you can
determine that two of the alternative answers are incorrect. For each of these questions you flip a fair
coin to decide whether you leave it blank or randomly guess one of the remaining three answers. Your
expected score for these six questions is:
(A) 5 (B) 6 (C) 7 (D) 8 (E) 10
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