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We can make a static measurement to deduce the spring constant to use in the model. If a 61 kg woman stands on a low wall with her full weight on the ball of one foot and the heel free to move, the stretch of the Achilles tendon will cause her center of gravity to lower by about 2.5 mm. What is the spring constant?
A. 1.2 × 104 N/m
B. 2.4 × 104 N/m
C. 1.2 × 105 N/m
D. 2.4 × 105 N/m
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