17. Eight unmarked envelopes contain the numbers 1, 2, 4, 8, 16, 32, 64, 128. Eve chooses several
envelopes randomly. Alice takes the rest. Both sum up their numbers. Eve’s sum is 31 more than Alice’s
sum. How many envelopes did Eve take?
(A) 2 (B) 3 (C) 4 (D) 5 (E) 6
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