A $3\mathrm{.}0-$kg block slides along a frictionless tabletop at $8\mathrm{.}0\frac{m}{s}$ toward a second block $($at rest$)$ of mass $4\mathrm{.}5$ kg $.$ A coil spring, which obeys Hooke's law and has spring constant $k=840\frac{N}{m},$ is attached to the second block in such a way that it will be compressed when struck. by the moving block. $($Figure $1)$

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$1$ of $1$