Given that the intial height is h = 3.00 m
The pulling length is x1 = 2.00 cm = 2.00*10-2m
The pulling length is x2 = 3.00 cm = 3.00*10-2m
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( if the bocy is in compressed position it has eleastic potential energy and at height h it has gravitational potential energy)
Apply conservation fo energy then we ger
(1/2)kx12 = mgh
where g = 9.8 m/s2 is the accelaration due to gravity
then we get force constant k = ----------- N/m
(1/2)kx22 = mgh2
then we get h2 = -------- m