A $4\mathrm{.}30$ g bullet moving at $871\frac{m}{s}$ strikes a $570$ g wooden block at rest on a frictionless surface. The bullet emerges, traveling in the same direction with its speed reduced to $414\frac{m}{s}.($a$)$ What is the resulting speed of the block? $($b$)$ What is the speed of the bullet$-$block center of mass?

$($a$)$ Number

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$($b$)$ Number

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