Block $2($mase $0\mathrm{.}40$ kg$)$ is at rest ont a trictiontess surfice and touching the end of an

wistretched spring. The other end of the spring le fixed to a wall, Block I $($mass $0\mathrm{.}70$ k$2)$ traveling at $4\mathrm{.}00$ m$/$&$,$ collides with block $2,$ and the two blocks stick together. The spring has a maximum compression of $30\mathrm{.}0$ em$.$ What is the spring constant $($N$/$m$)$ of the spring?

A$)38,7$

$8)127$

$0)216$

$0)90$

$8)79,2$