Question 1050919
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Physicists believe that lengthening of a spring is linear function of the applied force (of the weight in this case) 
if the lengthening is up to 2% - 3% (maximum 5% ?) of the spring initial length. 


Above that, the lengthening is not a linear function.


But in your problem the length of the spring is not given.


Therefore, I don't know how to give the answer.