import mx.transitions.Tween;
import mx.transitions.easing.*;
new Tween(instanceName, property, func, begin, finish, duration, useSeconds);
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this.onMouseDown = function() {
import mx.transitions.Tween;
import mx.transitions.easing.*;
new Tween(ball_mc1,"_alpha",Strong.easeOut,ball_mc1._alpha,Math.random()*100,20,false);
new Tween(ball_mc2,"_alpha",Strong.easeOut,ball_mc2._alpha,Math.random()*100,20,false);
new Tween(ball_mc3,"_alpha",Strong.easeOut,ball_mc3._alpha,Math.random()*100,20,false);
new Tween(ball_mc4,"_alpha",Strong.easeOut,ball_mc4._alpha,Math.random()*100,20,false);
new Tween(ball_mc5,"_alpha",Strong.easeOut,ball_mc5._alpha,Math.random()*100,20,false);
}