Движение Мувика!!!!!!

[Штрек]

mc._x = 100;
this.mc.onEnterFrame = function() {
if (this._x<=500) {
if (this._x>=250) {
this._alpha -= 2*100/(500-250);
}
this._x += 2;
} else {
delete this.mc.onEnterFrame;
}
};