[填空题]
A 4.2-m-diameter mers)wm jyh .hqf3dnr. f:o ax/k2af*8 w3ryhc.ir i3. n dxd;brw-6-go-round is rotating freely with an angular velocity of 0.8bdnr 6.iwc;x3-.dirh $rad/s$ Its total moment of inertia is 1760 $kg \cdot m^2$ Four people standing on the ground, each of mass 65 kg, suddenly step onto the edge of the merry-go-round. What is the angular velocity of the merry-go-round now? $rad/s$ What if the people were on it initially and then jumped off in a radial direction (relative to the merry-go-round)? $rad/s$