二元合金处于低共熔温度时,物系的条件自由度 :( )<br>·<img src="/lqwvjeImg/b4/b4f74f66265b98def5e88c870091d179.png"style="width:38px;height:20px;"><br>·<img src="/lqwvjeImg/3b/3bd4a8e9636f934addd7e139ce505f0d.png"style="width:35px;height:18px;"><br>·<img src="/lqwvjeImg/ec/ec4ba30421a29a6309f3c26d769eda7d.png"style="width:38px;height:20px;"><br>·<img src="/lqwvjeImg/31/313d22d5a5be0cc5f0cdf22fdbef7bd6.png"style="width:38px;height:18px;">