Members of a social club met to address 280 newsletters.If they addressed ~$\frac{1}{4}$~of the newsletters during the first hour and~$\frac{2}{5}$~ of the remaining newsletters during the second hour, how many newsletters did they address during the second hour?
28
42
63
84
112
没有注意是剩余的2/5,这个陷阱
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