拉杆式旅行箱可看成杠杆，如图所示．已知OA=1.0m，OB=0.2m，箱重G=120N，请画出使箱子在图示位置静止时，施加在端点A的最小作用力F的示意图，且F=_1N．

题干

拉杆式旅行箱可看成杠杆，如图所示．已知OA=1.0m，OB=0.2m，箱重G=120N，请画出使箱子在图示位置静止时，施加在端点A的最小作用力F的示意图，且F=____N．

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English club plan
How long to stay	⑴ days
The things to do	English listening, ⑵ , reading, writing and ⑶ .
Others rules	Not to bring ⑷ and ask for help by putting up the hands, take ⑸ with classmates and teachers here.

⑴____ A. six B. seven C. eight

⑵____ A. speaking B. pronouncing C. drawing

⑶____ A. running B. swimming C. playing

⑷____ A. money B. books C. phones

⑸____ A. pictures B. notebooks C. dictionaries