Two weights lie on a perfectly smooth table, the mass ratio of which is 1:3. The weights are interconnected by a compressed spring with stiffness k = 1000 N/m. The spring is held in a compressed state by a thin, inextensible thread. After burning the thread, the spring expands, and the lighter load acquires kinetic energy Wk = 60 J. Determine the amount of deformation of the compressed spring.

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