[单选题]
A rubber ball with a speed of 5.0 m/s collides head-on elastically withz62ls5 y. +yvnmaato8zt5x 4 z an ident v5az tsy .yox+6t2z8nm l5z4ajcw r vvqo 75 4hd*-is-:1zougical ball at rest. What is the speed of the initially stopped ball after the collisioswhj *1o45-i drqc7vgo:-zuv n?