从1，2，-3三个数中，随机抽取两个数相乘，积是正数的概率是______．

请纠正下面几条标题的错误并说明理由：

（1）深夜偷钓丧命  亡妻愤然上告

纠正错误：                                                                                                                                                         

说明理由：                                                                                                                                                         

（2）违规作弊有法可依了

纠正错误：                                                                                                                                                         

说明理由：