$17.$ The pitch of a broach determines the $\_\_\_$ of material removed with each tooth.

$18.$ The number of flutes on a milling cutter affects the balance between $\_\_\_$ removal and surface finish.

$19.$ A drill bit for milling is optimized for lateral cutting and thus has a different $\_\_\_$ design compared to standard drills.

$20.$ The $\_\_\_$ on a twist drill's tip is crucial for starting accuracy and cutting speed.