- 問題詳情:Earlyonemorning,morethanahundredyearsago,anAmericaninventorcalledEliasHowefinallyfellasleep.Hehadbeenworkingallnightonthedesignofasewingmachinebuthehadrunintoaverydifficultproblem:Itseemedimpossibletogetthethreadtorunaroundtheneedlewithoutany...
- 25599