AngularJS Select默认值？？

AngularJS Select绑定的是对象：

$scope.cars = { car01 : {brand : "Ford", model : "Mustang", color : "red"}, car02 : {brand : "Fiat", model : "500", color : "white"}, car03 : {brand : "Volvo", model : "XC90", color : "black"} };

<select ng-model<爱尬聊_让生活聊出新高度>="selectedCar" ng-options="y.brand for (x, y) in cars"></select>

现在想给select一个默认值怎么设置呢？

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Dark0613 19小时前

<option>--please select--</option>

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