[填空题]
A 4.2-m-diameter merrl p9q;5awfys 4:/0 xs5-pklzouawi0 my-g1 vztdn:ooh 8ms1kol 7o a4)b/o-round is rotating freely with an angular velocity of 0.8 m)o4zobh/oo8al ts:1vd71n k$rad/s$ 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)? $rad/s$