已知直角三角形的两直角边长分别为5cm和12cm,内切圆半径r=______.
2.
题目分析: 斜边==13cm,则此值角三角形的内切圆半径=cm.故填2.
He has already gone home. But before he left, he__________ all the mistakes in his translation.
A.had corrected
B.has corrected
C.corrected
D.would correct
《普通高中历史课程标准(实验)》在内容标准中使用了"知道""概述""分析"等行为动词,为了帮助学生达到"知道"层次,教师可选用哪些具体的方法(不少于四种)?