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Answer 1

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¡à  s₁ = v_o t₁ = 5¡Á0.4 = 2 m       £¨2·Ö£©

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¡à  s = s₁ + s₂ + s₃ = 2 + 1.2 + 0.09 = 3.29 m£¨1·Ö£©

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= [0.5£¨3 + 4£©/0.02 ] + 0.5¡Á10 = 180 N £¨1·Ö£©

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