如图所示裝置中，轻质杠杆支点为O，物块A、B通过轻质细线悬于Q点，当柱形薄壁容器中没有液体时，物体C悬挂于E点，杠杆在水平位置平衡；当往容器中加入质量为m₁的水时，为使杠杆在水平位置平衡，物块C应悬于F点。A、B为均匀实心正方体，A、B的边长均为a，连接A，B的细线长为b，B的下表面到容器底的距离也为b，柱形容器底面积为S。已知：a=b=2cm，S=16cm²，O、Q两点间的距离为L_OQ=4cm；三个物块的重为G_a=0.016N．G_B=0.128N，G_C=0.04N，m₁=44g； ρ_水=1.0×10³kg/m³，g=10N/klg，杠杆重力对平衡的影响忽略不计，细线重力忽略不计，物块不吸水。求：

①O、E两点间的距离L_OE=？

②E、F两点间的距离L_EF=？

③如果剪断物块A上方的细线，往容器中加水，直到容器中水的质量为m₂=120g，则物块处于平衡位置后，水对物块B上表面的压力F_b=？

    One day a famous teacher was walking with his student. On the way, they saw a lake. They stopped and the teacher told the student, “I'm thirsty. Get me some water from that lake.”

    Just when the student reached the lake, a cow was walking in the lake. So the water became very dirty. He thought “I can't give the dirty water to my teacher!”

    He came back and told the teacher, “The water is very dirty. We can't drink it.” After about half an hour, the teacher asked the student to get some water again. So he went back to the lake.

    But the lake was still dirty. So he told the teacher the same thing. After some time, the teacher asked him to go back again. But this time, he found the water was clear. The mud in the water came to the bottom. So he got some water.

    The teacher looked at the water and said to him, “You did nothing to make the water clear. You just let it be… Your mind is also like that! When it is bothered, just let it be. Give it some time.”