Answer:
2/5 and 3/5
Explanation:
Complementary events have probabilities that sum to 100%, or 1.
28+82 = 110; this is not 100.
10+80 = 90; this is not 100.
1/7+2/7 = 3/7; this is not 1.
2/5+3/5 = 1; this is correct.
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