Problem $19\mathrm{.}55$ Disk A initially has a counterclock wise angular velocity $0=50$ rad$/$s$.$ Disks B and C are initially stationary. At t $=0,$ disk A is moved into con tact with disk B$.$ Determine the angular velocities of the three disks when they have stopped slipping rela tive to each other. The masses of the disks are mA $=4$kg$,$mB $=16$ kg$,$andmC $=9$ kg$.($SeeActiveExample $19\mathrm{.}4.)$